The Problem of Hemisphere Defense

Immediately after the Munich crisis of September 1938, the United States moved toward a new national policy of hemisphere defense. Although one of the fundamental foreign policies of the United States was the Monroe Doctrine, with its admonition against any European or Asiatic political or military intrusion into New World affairs, the nation in the immediately preceding years had neither the desire nor the military means to engage in a unilateral defense of the Americas. After World War I the American people, influenced by the overwhelming preponderance of friendly naval and military power in western Europe, became increasingly isolationist and increasingly indifferent toward maintaining enough military strength to defend even their own continental and outlying territory against a strong adversary. The rise of aggressive dictatorships in Europe during the pre-World War II decade found the United States Army in condition to do no more than defend the continental United States, Oahu, and the Panama Canal Zone. The Navy, relatively much stronger than the Army, was tied down in the Pacific by Japan's naval expansion and aggressive action in China. Therefore, when President Franklin D. Roosevelt declared, six weeks after the Munich settlement, that "the United States must be prepared to resist attack on the western hemisphere from the North Pole to the South Pole, including all of North America and South America," 1  the Army and Navy were presented with a much bigger mission than they were then prepared to execute.

Until the President gave his "quarantine" speech the year before, on 5 October 1937, the avowed policy of the Roosevelt administration came near to being one of peace at any price, unless the United States was directly attacked. Under the circumstances, and in view of its own very limited strength, the Army at the beginning of 1937 held that its mission was confined to defense of United States territory against external attack, protection of the nation against internal disorder and insurrection, and maintenance, during peace, of a sufficient force to permit expansion to the extent de-


manded by an emergency.2  Current war plans did not envisage even the possibility of war with the European dictatorships. When, in the summer of 1937, with preludes to World War II already in progress in Spain and China, a War Department General Staff study expressed concern about the Army's state of preparedness for meeting "serious threats to the continental United States and its possessions," one officer underscored this clause and added the query: "How about threats to other nations in the Western Hemisphere?" His question remained unanswered.3

When President Roosevelt recommended a substantial increase in appropriations for the Army in January 1938, he defined adequate national defense as "simultaneous defense of every part of the United States of America" and stated, "we must keep any potential enemy many hundred miles away from our continental limits." 4  The President extended national defense policy in more specific terms in an address at Kingston, Ontario, on 18 August 1938. "I give to you assurance," he said, "that the people of the United States will not stand idly by if domination of Canadian soil is threatened by any other Empire." 5  His assurance recognized that the long unfortified border with Canada made it inevitable that the United States should consider Canadian defenses a part of the outpost line of its own continental defense system.

The President moved toward a broader policy as soon as he became convinced that the Nazis intended to liquidate Czechoslovakia. After listening to Adolf Hitler's broadcast on 12 September, President Roosevelt directed Harry L. Hopkins to make a personal survey of the west coast aviation industry and report on its capacity for expansion. Following the Munich agreement of 30 September, and particularly after Ambassador William C. Bullitt returned from France on 13 October with a firsthand report on the European situation, the President pressed an expansion of air strength with great vigor. The Hopkins survey, Mr. Bullitt's report, the urgings of Assistant Secretary of War Louis Johnson and of the new Chief of the Air Corps, Maj. Gen. Henry H. Arnold, and the President's own realization that the technological development of airpower now posed a threat to the United States from any hostile Western Hemisphere base, all combined to forge not


only a new military air program but also the prewar policy of hemisphere defense. Both program and policy were settled upon at a momentous conference on 14 November 1938, at which the President announced his immediate goal to be an Army air force of 10,000 planes and an aircraft productive capacity of 10,000 planes a year. Observing that "our national defense machine . . . was weakest in Army planes," the President went on to say, "we must have a large air force in being to protect any part of the North or South American continent, and we must have a sufficiently large air force to deter anyone from landing in either North or South America." 6  The next day President Roosevelt informed newsmen in general terms of what had been said at the conference, and specifically of the new determination of the United States to maintain continental security from Canada to Tierra del Fuego against any possible threat from other continents. In response to a direct question as to whether the problem of national defense had now become a problem of continental defense, the President answered: "Yes, but continental defense that does not rest solely on our shoulders."7

Hemisphere Security and the Axis Threat

As President Roosevelt recognized, the new national policy, and consequent military objective, , of hemisphere defense needed the friendly and active support of other American nations in order to be effective. During the Munich crisis, the Department of State had begun to plan the strengthening of what Assistant Secretary Adolf A. Berle termed "the north-south axis." 8  To the north, the way toward closer ties had already been prepared by meetings between the President and Canadian Prime Minister William La Mackenzie King and by informal military staff talks at the beginning of 1938.9  To the south, the United States availed itself of the general Pan-American conference that had already been scheduled to meet in Lima, Peru, in


December 1938. The goal of the United States at Lima was to secure the adoption of a "hemispheric foreign policy," and Secretary of State Cordell Hull succeeded in obtaining unanimous adherence to a declaration that "affirmed the intention of the American Republics to help one another in case of a foreign attack, either direct or indirect, on any one of them.10  The Declaration of Lima became the cornerstone for later negotiations to insure the political, economic, and military cooperation of the Latin American nations against the threats of Axis and Japanese aggression.

These threats seemed very real in 1938 and 1939- In early 1938 the Department of State compiled a catalogue of German and Italian activities and used it as a basis for urging the War and Navy Departments to adopt measures for closer military collaboration with other American nations.11  Rumors of Japanese interest in offshore islands along the Pacific coast of the Americas, reports of Japanese reconnaissance under the guise of "fishing" along the Mexican and Central American coasts, rumors of German interest in Samaná Bay in the Dominican Republic, reports of German plots to foment revolutions in Brazil, Uruguay, and Argentina-these were typical examples of items that induced a growing alarm in administration circles during 1938.12  In addition, Nazi and Fascist propaganda against the United States in Latin America was violent and ceaseless, and Nazi barter techniques and clandestine subsidization by the German Government were making deep inroads in the Latin American market. After summarizing the variety of activities in which the Axis Powers and Japan were engaging at the time of the Lima Conference, Secretary Hull wrote in retrospect:

To me the danger to the Western Hemisphere was real and imminent. It was not limited to the possibility of a military invasion. It was more acute in its indirect form of propaganda, penetration, organizing political parties, buying some adherents, and blackmailing others. We had seen the method employed with great success in Austria and in the Sudetenland. The same technique was obvious in Latin America.13

President Roosevelt took perhaps the broadest and most prescient view of the growing menace to the Americas. To a group of congressmen in February 1939, he expressed his opinion that war in Europe was almost certainly in the offing and that Hitler's immediate objective was the domination of Europe. But, he added, "as soon as one nation dominates Europe, that


nation will be able to turn to the world sphere." 14  Three months later, speaking to another Congressional delegation, the President reiterated his conviction that war in Europe was imminent, and he predicted that in the event of war there was an even chance that the Axis Powers would win over France and Great Britain. The President then went on to say:

In that case their first act would be either to seize the British Navy or put it out of action. Then they would establish trade relations with Latin America, put instructors in the armies, etc. They would probably not touch British, French or Dutch possessions in this hemisphere. But in a very short time we would find ourselves surrounded by hostile states. Further, the Japanese, who "always like to play with the big boys," would probably go into a hard and fast alliance. The combined German and Italian Navies were about the equal of ours and the Japanese was about eighty percent of ours. Therefore, the temptation to them would always be to try another quick war with us, if we got rough about their. South American penetration.15

It was this specter of a victorious Axis triumvirate dominating the European and Asiatic continents, rather than any immediate military threat to the security of the Western Hemisphere, that was grimly disturbing not only to the President but also to his military advisers as they turned to their task of formulating new war plans to cope with the menacing world situation.


The Army and Navy before 1939 had confined their war planning principally to calculating what they could do to meet a threatened attack on American territory by individual nations. Only the ORANGE plan, which dealt with the contingency of a Japanese attack, had much relevance in the light of the international situation at the end of 1938 and the new national policy of hemisphere defense. Anticipating the President's formal enunciation of the new policy, the joint Board on 8 November decided to instruct its joint Planning Committee to make a thorough investigation of the "various practicable courses of action open to the military and naval forces of the United States, in the event of (a) violation of the Monroe Doctrine, by one or more of the Fascist powers, and (b) a simultaneous attempt to expand Japanese influence in the Philippines." The planners were further told to base their study and recommendations on the assumptions:

(a) Germany, Italy, and Japan may be joined in an alliance.
(b) The action of any one or two of these Fascist nations will receive the sympathetic support of the others.


(c) Democratic nations will remain neutral as long as their possessions in the western hemisphere are unmolested.16

Such a survey would amount to a reassessment by the Army and Navy of what they could do in defense of the Western Hemisphere under the most unfavorable foreseeable development of world affairs.

The Joint Planning Committee went to work immediately on its exploration of the strategic position of the United States. An indication of the planners' approach to their task is contained in the following questions concerning cooperation with Latin America:

a. May cooperation with the United States be expected in the direction of resisting attempts by Germany, Italy, or Japan to dominate the internal political organization of these countries?
b. May similar cooperation be expected in the direction of resisting attempts to deflect the normal flow of trade away from the United States?
c. May similar cooperation be expected in the direction of resisting attempts to establish under any guise air bases or naval bases which may be used by the armed forces of either Germany, Italy, or Japan?
d. To what extent may it be expected that the active cooperation of the United States in resisting foreign encroachment or invasion would be welcome?
e. To what extent may it be expected that air base or naval base facilities would be willingly offered for the use of the United States in the defense of the Western Hemisphere?
f. What practicable air base and naval base facilities now exist in each of these countries, and briefly, to what extent are they susceptible to development?

After five months' intensive study, the planners submitted their final report to the joint Board on 21 April 1939. The board properly described the report as a monument to its authors, since it provided a sound and comprehensive estimate that served as a basis for the detailed strategic planning that followed. 18

With respect to the Atlantic situation, the joint Planning Committee concluded that Germany and Italy might be expected to encroach progressively in Latin America, initially through intensive economic penetration, then through political interference that might reduce Latin American governments to subservient or even colonial status, and finally through establishment of military bases. The first military move of the Axis Powers would probably be an attempt to occupy the area around Natal, on the eastern bulge of Brazil, in order to strengthen their strategic position in the South


Atlantic; subsequently, they might extend their military control to positions from which they could launch direct attacks on the Panama Canal. In the Pacific, Japan's objectives would be the seizure of the Philippines and Guam and the elimination of all Western influence from eastern Asia and the western Pacific. The report pointed out that, if Germany, Italy, and Japan were to strike simultaneously, their attacks would present the United States with a critical dilemma: Its existing naval power was certainly strong enough to fend off Germany and Italy in the Atlantic and possibly could be made strong enough to protect the American position in the western Pacific; it certainly could not do both simultaneously. The planners did not propose any solution to this dilemma-which, fundamentally, called for a choice between hemisphere defense on the one hand and defense of American territory and interests in the western Pacific on the other-but they did insist that priority must be given to protection of the Panama Canal and the Caribbean area, the position and region most vital to the defense of the United States.

The Joint Planning Committee ended its report of 21 April by recommending the measures that it considered most essential to the immediate improvement of American defenses. Briefly, these were the rapid completion of planned defense installations in Hawaii and the Canal Zone, steps to improve the security of the Panama Canal and to enlarge its locks, development of Alaskan and Puerto Rican defenses (neither of which had any worthy of mention at this time), development of Pacific naval bases, an increase in the Fleet Marine Force to fifteen thousand men, organization of a three-division emergency expeditionary force by the Army, and a rapid increase in naval strength, especially in vessels and aircraft for antisubmarine operations.

The Joint Board approved the report on 6 May 1939 and ten days later directed the joint Planners to begin work on a series of war plans that would match the varying situations that might develop. For planning purposes, this directive defined the Western Hemisphere "as including the Hawaiian Islands, Wake Island, American Samoa, and the Atlantic Ocean as far east as the 30th Meridian of West Longitude." The general concepts for each of five alternate RAINBOW plans were determined by the end of June, and RAINBOW 1, the basic plan, received official Army and Navy approval in August and President Roosevelt's assent in October. RAINBOW 1, the projected RAINBOW 4, and supplementary plans that evolved from them provided the principal bases for Army defense preparations until 1941.

RAINBOW 1 called for the protection of all United States territory (but no reinforcement of the Philippines) and of the remainder of the Western Hemisphere north of latitude 10° south, a line that bisects South America,


just below the Peruvian and Brazilian bulges. In accordance with the joint Board's basic directive of November 1938, RAINBOW 1 assumed that the democracies of Europe and Latin America would remain neutral and that United States forces alone would be available to resist an attack. In contrast to RAINBOW 1, RAINBOW 2 and RAINBOW 3 envisioned active defense of American interests in the western Pacific. RAINBOW 4 was similar to RAINBOW 1, a principal difference being that it called for protection of the entire Western Hemisphere. RAINBOW 5 envisaged a war in which the United States would act in concert with Great Britain and France; in addition to doing all of the things called for in RAINBOW 1, RAINBOW 5 contemplated the dispatch of American forces "to either or both of the African or European continents in order to effect the defeat of Germany, or Italy, or both." So far as hemisphere defense measures were concerned, there was little difference among the RAINBOW plans of 1939- Each allotted the Army and Navy the primary task of defending the Western Hemisphere against military attack from the Old World; when the successful accomplishment of that task had been assured, American forces might then engage in offensive operations, either alone or in concert with those of other powers, against the aggressor nations.19

The Problem of Bares

The Joint Board's approval of the first RAINBOW plan in August 1939 brought to the fore the problem of securing permission for American forces to use military base facilities in other Western Hemisphere nations and in European possessions in the New World. To carry out the hemisphere defense missions of the Army and Navy as outlined in RAINBOW 1 the planners agreed that, in addition to new defenses recommended for Alaska and Puerto Rico, it was also necessary to obtain use of limited base facilities in various British possessions (Trinidad heading the list), in Brazil (at Natal and at other points on or adjacent to the Brazilian bulge), along the northern coast of South America (in Colombia and Venezuela), at Guayaquil in Ecuador and on Cocos and the Galápagos Islands, and at Samaná Bay in the Dominican Republic. Admiral Harold R Stark, the new Chief of Naval Operations, sent a copy of RAINBOW 1 to Under Secretary of State Sumner Welles on 14 Au-


gust 1939 and asked the Department of State to enlist the cooperation of the nations concerned in making available base facilities for American military operations at the points enumerated. Steps in this direction were taken immediately after the outbreak of war in Europe in September 1939.20  The British agreed to a limited use of base facilities in Bermuda, St. Lucia, and Trinidad by United States Navy vessels and aircraft assigned to the neutrality patrol of Atlantic waters; and the Department of State arranged with some of the Caribbean nations for emergency use of their facilities.21

The question of acquiring new base facilities in the Western Hemisphere had been explored on various occasions before August 1939. In a thorough canvass of the problem in 1936, prompted by Congressional proposals to annex European possessions in return for cancellation of World War I debts, the Army came to the conclusion that no move of this sort would be wise. The Army assumed that it was against national policy to acquire new territory except for urgent strategic reasons. It also assumed that the Latin Americans would resent the territorial expansion of the United States within the Western Hemisphere, either in their own territory or in the possessions of the European powers. Any such move by the United States would be certain to raise anew the cry of "Yankee Imperialism" and undermine the friendly relations recently established through the "Good Neighbor" policy. The Army examined in turn every colonial area in North and South America and concluded that none of them had a military value sufficient to offset the disadvantages of American ownership. On the other hand in 1936, as well as later, the Army expressed its strong opposition to the transfer of any existing European possession to another Old World power. 22

The United States had taken a particular interest before 1939 in the Galápagos Islands, owned by Ecuador and located about 1,000 miles southwest of Panama. These undefended and almost uninhabited islands in hostile hands could become a serious threat to the Panama Canal. Conversely, an American base there would permit a wide aerial reconnaissance of the Pacific to guard against a naval attack on the Canal. Rumors circulated in the fall of 1938 that Ecuador wished to sell the Galapagos to the United States. At the beginning of 1939, Maj. Gen. David L. Stone, the commanding general


of the Panama Canal Department, recommended that the United States purchase both the Galapagos Islands from Ecuador and the intervening Cocos Island from Costa Rica, on the ground that they were essential to defense of the Canal. The War Department at first favored General Stone's recommendation but subsequently had to disapprove it because of the Navy's opposition and for broader political reasons. It also disapproved his later suggestion that the United States secure base facilities in these islands through a long-term lease.23

While General Stone's recommendation with respect to the Galapagos was under consideration in Washington, Under Secretary of State Welles called President Roosevelt's attention to unconfirmed reports that Chile might be willing to sell Easter Island to the United States .24  The President, noting that Easter Island was "a definite possibility as a stopping place for trans-South Pacific planes," stated, "it should, therefore, under no circumstances, be transferred to a non-American power." 25  Two months later, Under Secretary Welles announced the same principle with respect to the Galápagos Islands when he informed Congress, "any endeavor on the part of any non-American power to purchase or lease the Islands or to use any part of them for a naval, military, air, or even a commercial base under whatever terms would be a matter of immediate and grave concern to this Government." 26  These statements amounted to a strong reaffirmation of the nontransfer principle of the Monroe Doctrine, a principle so basic in prewar planning for hemisphere defense that Army officers sometimes defined the doctrine in that term alone.

From the viewpoint of the armed services, the most serious and pressing base problem in the summer of 1939 was that of securing the right to establish air and naval base facilities at or near Natal in Brazil, as proposed in RAINBOW 1. The developing range of aircraft made Brazilian territory at this point easily accessible from the western bulge of Africa and its adjacent islands. The Military Intelligence Division (G-2) estimated in midsummer of 1939 that Germany and Italy then had more than 3,000 planes capable of flying the South Atlantic with a bomb load .27  Northeastern Brazil had no


land defenses, and in 1939 Brazilian land, sea, and air forces were wholly incapable of defending the Natal area against overseas attack. The Army and Navy agreed that a base at Natal was essential for the effective defense of the South American continent. In March 1939 the Navy urged "the absolute necessity for a base of operations in or near the eastern extremity of South America in case the South Atlantic is to be controlled by any force." 28  Three months later, in June, the Army's Air Board termed an air base at Natal a fundamental requirement for defense operations in South America.29  One of the strongest arguments in favor of the projected Natal base was that if United States forces were sent there first, a hostile military expedition would find it difficult if not impossible to dislodge them, nor could German or Italian forces launch a major attack against any other part of the South American continent while the Brazilian bulge was protected by American forces; on the other hand, if Axis forces established themselves on the bulge first, it would require a formidable effort to dislodge them.30  Despite the priority of Natal on the list of desired bases, it took nearly three years of delicate and involved political and military negotiations to secure Brazilian permission to station United States Army forces in the area.31

Except for its interests in the Galapagos Islands and Natal, the Army in 1939 was less concerned than the Navy with proposals to acquire the use of foreign areas for defense purposes. During May 1939, for example, the War Department held that neither Greenland nor the Dutch West Indies had sufficient military value to warrant their purchase. 32  The Air Board report of June recommended the establishment of an Army air base on Trinidad as well as at Natal,33  but the Army was more immediately interested in the development of an air base on Puerto Rico, essential for the defense of the eastern approaches to the Caribbean and as a steppingstone toward South American air bases. When a deceptive stalemate followed Hitler's quick triumph over Poland, agitation by the Army and Navy for base expansion subsided, although planners continued to think in terms of hemisphere defense operations by United States forces with access to such strategic base sites as might be necessary.


The Army's State of Readiness in 1939

The War Department in Washington headed the Army's command organization for planning and directing the new operations for national and hemisphere defense that were in prospect in the summer of 1939. The War Department consisted of the Secretary of War's Office, the Office of the Chief of Staff assisted by a General Staff of five divisions, and the headquarters of the arms and of the technical and administrative services in the national capital. Although the Secretary of War exercised general administrative control over all Army activities, the Chief of Staff actually commanded the military forces at home and overseas and (from July 1939 onward, as required) reported directly to the President on matters relating to strategy, tactics, and operations.34  Of the General Staff divisions, the War Plans Division was the one most immediately and extensively concerned with planning and supervising new military operations; eventually it evolved into a wartime command post for the Chief of Staff, replacing the General Headquarters contemplated in the plans of 1939 and partially activated in 1940 and 1941.35  Below the War Department, the command and administration of Army ground forces in the United States were exercised through nine corps area headquarters, and (after 1 July 1939) four department headquarters of similar character contained most of the Army's overseas forces. The continental air forces came under the General Headquarters Air Force, established in 1935, and the continental ground forces for certain purposes were under four army headquarters, which were designed to become command headquarters in time of war. 36

The adoption of a new policy of hemisphere defense did not change the Army's basic mission of protecting the continental United States against military attack. Col. Frank S. Clark, a co-architect of the RAINBOW plans and principal Army planner, emphasized this point in early 1940 when he wrote: "The primary and inescapable requisite in our Doctrine for the conduct of any war is the necessity that wherever and whatever operations may be in-


dicated, no commitment of our armed forces shall be permitted to impair the defensive security of the continental United States." 37  Because the mobility of the United States Fleet between the Atlantic and Pacific Oceans was a cornerstone of continental defense plans, the Army considered its mission of guarding the Panama Canal as secondary only to continental defense. In surveying the situation in 1939, Army and Navy planners decided that the continental United States and the Canal Zone could only be subjected to invasion or large-scale surface attack if such an attack was backed by airpower. Airpower in strength could not be projected directly across the oceans, but it could be launched from land bases within the Western Hemisphere. Therefore, the primary objective of the hemisphere defense policy, from the Army's point of view, was to prevent the establishment of any hostile air base in the Western Hemisphere from which the continental area or the Panama Canal might be bombed or from which a surface attack or invasion might be supported.

Between 1935 and 1938, before the adoption of the new hemisphere defense policy, the Army had been materially strengthened both in numbers and equipment in comparison with its situation during the early depression years. In active strength it numbered 189,867 individuals in military service on 30 June 1939.38  During June Congress appropriated funds to enable the Army to increase its enlisted strength during the following fiscal year to 210,000, a figure that became the "authorized strength" of the Regular Army after 1 July. As of June 1939, the Army's mobile ground combat forces in the continental United States numbered about 82,000 and included four partially filled infantry divisions, two small cavalry divisions, six separate brigades "in various states of completion," and only a few specialized supporting units. Although these "field forces" were theoretically available for deployment to meet any threatened attack, the Army in fact did not have a single division among its continental forces ready for immediate action.39

The major Army overseas garrisons, in the summer of 1939, were the Hawaiian (21,475), Panama Canal (13,451), and Philippine (10,920) Departments. The principal ground combat units overseas were the Hawaiian Division guarding the island of Oahu, the Philippine Division in the Far East, and two infantry and two artillery regiments in the Panama Canal Zone. The new department activated in Puerto Rico on 1 July had an initial strength of


less than 1,000; Alaska, attached to the Ninth Corps Area, had less than 500. In theory, the Alaska-Hawaii-Panama-Puerto Rico line constituted the Army's "outpost" line for the defense of the "main position," the continental United States.40  The direct primary mission of these outposts was the protection of naval bases and other installations-most notably, of course, the Panama Canal-needed to maintain the Navy's freedom of action.

Before 1939 the Army had developed basic plans for expanding its forces if war threatened. Its principal reserves in 1939 were the National Guard, numbering approximately 200,000, and the Officers' Reserve Corps, which had a strength of about 110,000. The first stage in expansion called for the creation of an Initial Protective Force of 400,000, to be obtained by inducting the National Guard into federal service. The Army had the immediate supply goal in early 1939 of accumulating all types of munitions for the Initial Protective Force and of acquiring reserves of critical (that is, noncommercial) items for the larger mobilization contemplated in what was called the Protective Mobilization Plan. Under this plan, the initial force would be increased to a strength of 1,000,000.

Until 1939 basic strategic plans for guarding the continental area in an emergency provided for concentrating most of the mobile combat units in the United States into strategic reserves and seacoast defense forces of approximately equal strengths. These strategic plans were designed, as a War Department memorandum of October 1938 put it, to "avoid the fatal error of distributing our limited forces in- a weak cordon along all our frontiers" and to "maintain the maximum concentration of forces for effective defensive operations in the area where the major hostile threat develops." 41  The hemisphere defense plans of 1939 and after also contemplated building up a strategic reserve of ground and air forces in the United States; but, instead of employing a large portion of the mobile forces for defense of continental coastal and land frontiers, the Army now planned to send them out in expeditionary forces as necessary to guard the hemisphere as a whole. This amounted to an extension of the main military position from continental to hemisphere frontiers. The principle of concentrating as many forces as possible in a strategic reserve was to be applied between 1939 and 1941 with particular rigor to the air forces, the first Army element to expand under the impetus of the new hemisphere policy.

Before President Roosevelt presented his recommendations for strengthening the Army's air arm to Congress in January 1939, he agreed (with con-


siderable reluctance) to a much more modest figure than the 10,000-plane goal he had previously advocated. Accordingly, he requested a $300,000,000 appropriation to provide at least 3,000 more planes for the Army. Congress in its enabling and appropriations acts of April and June 1939 provided the authorization and funds to permit the Army to embark on an expansion of its air arm to be completed by midsummer of .1941. This first "hemisphere defense" air program provided for an initial doubling of Air Corps personnel strength and an eventual airplane strength of 5,500 (including 3,300 combat planes), and for the replacement of most of the existing equipment. At the time (June 1939), the Air Corps had about 1,700 planes. Actually, many months were to elapse before the air arm received much strengthening in equipment. At the end of 1939, its airplane strength was only 1,800; and by the following May, the Air Corps had received only 1,350 new planes.42  By then, too, the national policy of sharing airplane production with Great Britain and France was in full swing and was threatening to delay the completion of the Army's own air program on schedule

While the new air program was taking shape, the War Department in March 1939 appointed an Air Board to consider the means by which the Air Corps should carry out its enlarged mission. The board, headed by General Arnold, Chief of the Air Corps, completed its labors in late June. It recommended the addition of four new major air bases to the eight already in existence, the deployment as soon as they were available of about 2,000 combat planes in tactical units at home and overseas (with about 1,300 more in reserve), and an Air Corps personnel strength of 49,000.43  For the continental United States, the Air Board proposed the establishment of new major air bases in the northeast arid southeast to bolster the air defense of the entire Atlantic seaboard of the United States and Canada. The northeast air base -- Westover Field, subsequently provided near Holyoke, Massachusetts-would permit long-range patrol and bombardment action to prevent the establishment of hostile air bases in eastern Canada and Newfoundland. The southeast air base -- MacDill Field, established later near Tampa, Florida-would permit the projection of Army air power to the eastern Caribbean and


provide the third corner, with Panama and Puerto Rico, for a triangular air defense coverage of the whole Caribbean area.44

Overseas, the new "hemisphere defense" air program called for the air reinforcement of the Panama Canal and Hawaiian Departments and for the establishment of new major air bases in Alaska and Puerto Rico. The Air Board also forecast the probable necessity for a major Army air base at Natal, Brazil, with intermediate staging bases connecting the Canal Zone, Puerto Rico, and Natal. Before the board completed its report the new air base for Puerto Rico had been approved, and the War Department planned to furnish it with enough long-range airpower to cover the eastern approaches to the Caribbean. Panama, which the War Plans Division described in May as "the Keystone in the defense of the Western Hemisphere," was to have the greatest overseas air strength, with the primary defensive mission of preventing the aerial bombardment of the Canal and the offensive mission of forestalling the establishment of any hostile air base in Central or South America within bombardment range of the Canal Zone. Army airpower in Hawaii, which War Plans termed "the indispensable bulwark" for the defense of the Pacific coast, was to be built up to a strength sufficient to insure the retention of Oahu as a base for the United States Fleet. Alaska, in the 1939 plans, was to be provided with a major air base from which the Army could interdict the establishment of any hostile air base in Alaskan territory and also cover the northern flank of the Hawaiian establishment. These plans, if fulfilled, would give some meaning to the idea of an "Alaska-Hawaii-Panama" defensive triangle, a concept that meant little as long as Alaska had no military or naval defenses. The plans of 1939 envisaged no reinforcement of the slender Army air strength in the western Pacific.45

In prewar theory, the Army's overseas garrisons were supposed to be provided in peacetime with enough forces to deal with any emergency or war situation, but in planning the deployment of the new strength to be acquired under the air expansion program, the Air Board had to acknowledge the impossibility of providing each overseas base with enough airpower to meet any foreseeable need. Instead, it proposed to pool as much air strength as possible in a central reserve in the continental United States, to keep the air strengths at overseas bases at a bare minimum, and to reinforce them from the continental reserve in an emergency.46  This was a sound proposal, but


when Pearl Harbor plunged the United States into war even the key bastion of Hawaii had fewer combat planes than the "bare minimum" planned for it in 1939.47

Though the United States Army in the summer of 1939 was stronger and better prepared for action than it had been in the earlier 1930's, it was numerically far weaker than the army of any other world power. On the other hand the United States Navy, somewhat favored over the Army in the initial rearmament program, had a strength just below that of Great Britain. While Japan's ominous naval expansion was making protection of American interests in the Pacific an increasingly formidable task, the Navy in general was ready to perform its traditional function of providing the first line of defense in a war emergency. Nor can the military power of the United States in 1939 be reckoned solely in terms of active Army and Navy strengths. Both services had partially trained reserve components, and the nation's industrial might constituted a tremendous military asset. As World War II was to show, the military potential of the United States exceeded that of any other nation.

Preparedness Measures: April-September 1939

In 1939 the American defense problem was one of planning to meet any immediate threat with existing means, and of expanding those means as rapidly as public sentiment permitted and circumstances required to enable the armed forces to execute their new mission of hemisphere defense. The new Air Corps program was the first move in this direction. The second was initiated about the time that the joint Planning Committee completed its exploratory study of the strategic situation in April 1939, when the Chief of Staff instructed his advisers to investigate the methods that the Army should employ to improve its state of readiness "in the event that war develops in Europe." 48  After consulting with the other staff divisions, the War Plans Division on 20 April recommended:

1. An increase of 40,000 in the Regular Army's strength to enable the Army to form "a small, balanced striking force immediately available for employment in support of our national policy in the Western Hemisphere."
2. The completion of the procurement of critical items for the forces to be provided by the Protective Mobilization Plan.


3. An increase in the National Guard to full peace strength.
4. The recruitment of personnel from the Civilian Conservation Corps for the Regular Army.
5. Various additional measures, designed to improve the readiness of the National Guard and Reserve components for employment in an emergency.

War Plans also emphasized the "immediate and vital importance" of carrying out the first and second of these recommendations.49  A further exploration of the expeditionary force proposal indicated that with its existing strength the Army could organize a mobile striking force of about 44,000, built around four streamlined peace-strength infantry divisions. With the recommended augmentation of the Regular Army, a force of 63,000 could be formed.50  No action was taken on these proposals until August, when the civilian and military authorities became convinced of the imminence of war in Europe.

In early August President Roosevelt made a decision concerning the United States Marine Corps that had an important bearing on subsequent Army preparations for defense. The President directed that the marines be withdrawn from Hawaii, the Canal Zone, and "all like places-the Army to take them over"-and that henceforth Marine Corps units would be used only for emergency occupation forces in such places as Bermuda, Trinidad, and Wake Island. Since the marines were thus designated the prime expeditionary force, the Army was required thereafter to give them top priority in the supply of certain types of Army equipment and ammunition.51

With the President and Secretary of State both on vacation, Acting Secretary of State Welles called an interdepartmental meeting on 17 August, at which he announced, "-the European situation is now so bad that I think we ought to be ready for the worst." 52  This was the signal for the Army to set in motion a series of "Immediate Action Measures," already drafted and based to a large extent on the proposals made the preceding April. By 21 August the Army had decided what should be done as soon as the European war began. It wanted to increase the Regular Army to an enlisted strength of 280,000 (the full peacetime strength prescribed by the National Defense Act of 1920), to recruit the National Guard to full peacetime strength (also 280,000 enlisted) and double its training hours, to procure as rapidly as possible all of the items of equipment and munitions needed for the Protective


Mobilization Plan force, and to reinforce overseas garrisons and speed up their current construction programs. In transmitting these proposals to the President, Secretary of War Harry H. Woodring explained, "the purpose of the measures as a whole is to place the Regular Army and the National Guard in a condition of preparedness suitable to the present disturbed world situation." "They do not," he added, "contemplate mobilization at this time but proceed only to the extent of completing its most important features." 53

In the early morning hours of 1 September 1939, the Army flashed word to its commanding generals at home and overseas that fighting had begun on the Polish border. Four days later, General George C. Marshall, the new Chief of Staff, announced that the President had approved an immediate increase in the Regular Army to the "National Defense" strength of 280,000-an announcement that proved premature, for the President actually confined his approval to a more modest increase that raised authorized enlisted strength to 227,000.54  The President also authorized a National Guard increase to 235,000 enlisted strength, and his proclamation of a limited emergency on 8 September allowed the War Department to step up both the armory and the field training of the Guard.55

Immediately after the war began, the Army made a variety of other moves to cope with possible emergencies. The Chief of Staff on 5 September confirmed the reinforcement of the overseas garrisons; air reinforcements for the Canal Zone had already departed, and ground units for this and other overseas outposts followed as rapidly as transportation could be provided.56  The commanding general of the Panama Canal Department was placed in charge of all Army activities-civilian as well as military-in the Canal Zone.57  On instruction from the President, the Chief of Staff notified the Chief of Naval Operations that arrangements had been made for Army Air Corps reconnaissance and bombardment planes to be available on call to the Navy to assist


in offshore defense of the Atlantic, Gulf, and Pacific coasts.58  The War Department directed the commanding general of the Sixth Corps Area to begin a military guard of the Sault Ste. Marie Canal and its locks, and within a week a number of defensive measures were in effect there.59  All corps area commanders were told to prepare plans for troop protection of industries engaged in military production.60  The beginning of a general European war, as these measures testify, had the effect of alerting the Army on many fronts.

The Army's "Immediate Action Measures" were but one phase of a broad program charted by President Roosevelt and his advisers on the eve of the European war. The fundamental objective set for national policy was to keep the United States out of the war. In order to achieve that objective, the United States had to keep the war out of the Western Hemisphere.61  But in addition the administration also wished to buttress the military power of Great Britain and France. Should the democracies of western Europe be defeated, the President and his aides foresaw an inevitable conflict between the United States and dominant European and Asiatic dictatorships. The President's greatest initial concern was, therefore, to secure a revision of the existing neutrality acts. After a hard struggle, Congress passed a new neutrality law on 4 November 1939, which permitted Great Britain and France (as well as any other belligerent) to obtain American arms on a "cash and carry" basis.

During August the President in consultation with the Department of State had decided upon more positive measures for keeping a European war away from the Americas. As soon as the war began, the United States would call a conference of the American republics to confirm the front of "continental solidarity" agreed upon at Lima the preceding December. The President also planned to institute an offshore patrol by the United States Navy designed, as he told Assistant Secretary of State Berle in late August, "to prevent an attack on any European colony in the New World, all the way from Canada to Guiana." He proposed to warn European belligerents to keep their warships on the other side of the Atlantic and, if they failed to do so, "he would then direct the Navy to make sure that no vessel came on this side of the Atlantic." 62  When news of the German attack on Poland reached the Presi-


dent, he immediately instructed the State and Navy Departments to arrange for a Pan-American gathering and to establish the neutrality patrol. The patrol was to operate in a neutrality zone, within limits to be approved at the conference. President Roosevelt himself decided on 3 September that the zone should extend approximately three hundred miles seaward from the American continents.63

Immediately after Great Britain and France declared war on Germany on 3 September, invitations were dispatched to the Latin American nations for a conference to be held in Panama. The Panama Conference opened on 23 September, with Under Secretary of State Welles heading the United States delegation. Before its adjournment on 3 October, the conference adopted resolutions embodying principles of neutrality and provisions for inter-American political and economic cooperation that were completely satisfactory to the United States. Resolution XIV, usually known as the Declaration of Panama, provided for the establishment of the Neutrality Zone, from which all belligerent warships were to be excluded, extending about three hundred miles seaward from the Canadian-American boundary in the Atlantic, around North and South America to the Canadian-American boundary in the Pacific. Each nation was authorized to patrol waters adjacent to its own coast to secure compliance with this resolution. The conference also established inter-American neutrality and economic committees. Both committees began their sessions in the fall of 1939 and made it their business to help maintain the common policies on neutrality agreed upon at the conference and to consider the economic problems that war in Europe was certain to bring, especially to Latin America. The final resolution adopted at the Panama Conference paved the way for a conference at Havana in July 1940. It provided "that in case any geographic region of America subject to the jurisdiction of any non-American state should be obliged to change its sovereignty and there should result therefrom a danger to the security of the American Continent, a consultative meeting such as the one now being held will be convoked with the urgency that the case may require." 64

While the Army had no direct hand in convening the Panama Conference, its spirit and actions were of vital importance to the development of closer military relations with Latin America. The cordial agreement among the American republics at Panama also indicated the probability of their co-


operation in emergency military measures deemed necessary by the United States in carrying out its plans for hemisphere defense. The conference's creation of the Neutrality Zone was less successful. Only the United States had the naval strength to carry out an effective patrol in waters adjacent to its coasts. The British naval operations that led to the self-destruction of the German pocket battleship Admiral Graf Spee in Uruguayan waters in December 1939 highlighted the ineffectual character of the Neutrality Zone around South America. In 1940 the United States abandoned the idea of a specifically limited neutrality zone and adopted instead a policy of patrolling Atlantic waters as far out to sea as circumstances of the moment dictated. Under this revised policy the United States extended its patrolling to the mid-Atlantic in 1941.65

The Navy's neutrality patrol of the Atlantic coast went into action in early September 1939. The President himself helped Admiral Stark draft the initial operations plan on 3 September. By mid-October the Navy was operating a continuous patrol about two hundred miles offshore from Newfoundland to the Guianas. As its means increased, the Navy extended its patrol outward toward the 60th meridian of longitude and well beyond the three-hundred-mile limit; by January 1940 a patrol force operating out of Norfolk was covering western Atlantic waters as far east as Bermuda. To strengthen the patrol, the President ordered the overhaul of forty World War I destroyers-the beginning of a reconditioning program that was to make fifty of these vessels available in time for the destroyer-base exchange with Britain in 1940. By early December the forty destroyers were all engaged in the Atlantic patrol. The Navy conducted a patrol inside the Caribbean Sea and Gulf of Mexico as well as on the ocean, the Department of State in certain cases arranging for "collective patrolling" with the Latin American nations concerned. The effectiveness of the patrol was limited in part by the relatively meager naval strength then available in the Atlantic; it was also limited by the fact that patrol vessels were authorized only to report the location of belligerent warships or suspicious vessels and to keep track of them. The President on 9 October 1939 ordered the Navy to broadcast reports of sightings in plain English, a step that probably helped to persuade the German Navy to keep its submarines and surface raiders out of the western North Atlantic during the early months of the war. The Atlantic patrol continued in varying forms in 1940 and 1941 and was increasingly extended with the acquisition and development of the British bases and with the heightening tension of the Battle of the Atlantic. After the establishment of the At-


lantic Fleet in February 1941, the Navy prepared to play a more active role in that contest.66

The naval patrol of Atlantic waters was not the only measure taken to keep belligerent action away from hemisphere shores. As an additional precaution, the President instructed the Department of State to maintain close surveillance over belligerent merchant vessels in Latin American ports and to report any suspicious movement or activity to the Navy. In practice, this surveillance seems to have amounted to a close watch on the seventy-five German merchant vessels caught in Western Hemisphere ports at the outbreak of war. The purpose, presumably, was to prevent these ships from rendering aid to German naval vessels in western Atlantic waters.67

The Strategic Outlook: Autumn and Winter, 1939-40

While the outbreak of war had the effect of initiating a variety of preparedness measures, the sequence of events in the late summer and fall of 1939 seemed to lessen the imminence of a military threat to the United States and other portions of the Western Hemisphere. In the first place, and contrary to the basic assumption of RAINBOW 1, Great Britain and France had accepted Hitler's challenge by declaring war. The British and French Navies now barred a Nazi move by sea against western Africa or South America; and Canada's declaration of war on 10 September put the northeastern front of the hemisphere on the alert. Secondly, after Germany's quick triumph over Poland, the European war settled into a lull that remained unbroken until April 1940. Pending a showdown between Germany and Anglo-French military power, there could be no real threat to the Americas. Finally, the Soviet-German pact of August 1939 had considerably reduced the chances of an early clash between Japan and the United States in the Pacific. With the Soviet Union freed for the moment from involvement in the European war, the Japanese were plainly frightened by the prospect of a Soviet attack in the Far East. While not restricting their aims and actions


against China, for the time being the Japanese adopted a policy of strict neutrality toward the European war and a more circumspect attitude toward the Far Eastern interests of the Western Powers. 68  The general effect of these developments was to slow down the tempo of the Army's defense plans and preparations in the fall and winter of 1939 and 1940.

During that period the sympathies of the great majority of the American people were unquestionably with Great Britain and France. But even more evidently, the public wanted to avoid direct participation in a European war. President Roosevelt and his advisers had the same goal. Sometime during September 1939, when the President was shown a draft of one long-range scheme for military expansion, he is reported to have said: "Whatever happens, we won't send troops abroad; we need only think of defending this hemisphere." 69  The President and his aides likewise foresaw that no serious threat to the Western Hemisphere could arise unless the British and French were pushed to the brink of defeat. In that event the United States would be faced with the grim choice either of supporting Great Britain and France, "as our outlying defense outposts," or of vastly increasing American naval power to "meet the ultimate issue between us and a Russo-German Europe bent on dominating the world, somewhere in the Middle Atlantic." 70  In an informal discussion on 19 September, the President and Assistant Secretary of State Berle

. . . ranged the globe, forecasting the division of Eastern Europe between Germany and Russia, wondering whether Western Asia was also to be divided, and guessing at the chance of an ultimate German foothold in the Atlantic. Both thought that if Germany won the war, Hitler would try to get his hands on the Azores or Cape Verde Islands, as bases for operations against the Americas. But both agreed that the war's main danger to this country lay in the alternative prospects of post-war economic chaos or a world economy dominated by the dictatorships.71

No evidence has yet been uncovered of an actual German plan in 1939 for military expansion toward the Americas, though some Nazi leaders talked vaguely about the ultimate clash that might follow a German triumph in Europe. Pending that triumph, German interest coincided with American opinion in seeking to keep the United States officially neutral toward the European war. 72


Army planners also recognized in late 1939 that no major threat to the Western Hemisphere was likely under the existing situation. As a War Plans Division strategic study of December 1939 put it, "as long as major wars continue in Europe and Asia, this hemisphere is in very little, if any, danger of attack." But, the authors of the study hastened to add, "experience has shown how quickly a situation can change and the impossibility of preparing for a new situation after it has developed." The most adverse change in the situation foreseeable would be the defeat of Great Britain and France. If they were defeated, a major hostile force might be able to gain a toehold somewhere along the Atlantic coast of North or South America. "The prevention of the establishment of major hostile forces," the study concluded, "will be far less difficult than their expulsion when established, and . . . our efforts should be directed toward such prevention."73

Colonel Clark of the War Plans Division in October 1939 wrote a penetrating analysis of the possible consequences of an Anglo-French defeat. He noted that, with the destruction of Anglo-French naval forces or their surrender to Germany, the United States would in time be faced with an extremely menacing situation, threatened by Japanese naval power in the Pacific and by German naval superiority in the Atlantic. Since it did not seem probable that Germany could win such an overwhelming victory without temporarily exhausting its military power, a considerable time would elapse before the Germans could launch a major attack across the Atlantic. In the meantime, they would undoubtedly step up their activity in Latin America. They might attempt to pave the way for later direct action by first overthrowing governments friendly to the United States. In any event, the United States would have to resist every effort that Germany might make to acquire British or French possessions in the New World. Colonel Clark also foresaw the possibility of a German attempt to block the Panama Canal by sabotage or air bombardment while the bulk of the United States Fleet was in the Pacific, but he considered this an unlikely development unless Japan acted in concert with Germany in launching an attack. He ended his analysis with the observation that any estimate based upon a common-sense evaluation of the prospective strategic situation might very well be meaningless. "The outstanding menace to civilization today," wrote Colonel Clark, "is the fact that the human and physical resources of the German state are being controlled by Hitler and a small group of equally unscrupulous and abnormal associates, activated almost entirely by the purpose of increasing and perpet-


uating their own personal power." This being so, Hitler might very well launch an attack on the New World "in disregard of the demonstrable best interest of the German nation."74

Both Japan and Germany had the physical means in 1939 to launch air attacks against the Western Hemisphere. Japan had eight aircraft carriers, built or building, from which it could launch hit-and-run attacks or. American positions in the Pacific. The War Plans Division believed that an attack of this sort was highly improbable so long as the bulk of the United States Fleet was in the Pacific. Germany lacked carriers, but it was believed to have a large bomber force capable of spanning the South Atlantic from African bases to the Natal area of Brazil. In re-estimating the Army's requirements for airpower in December 1939, the War Plans Division based its calculations on the air strength that would be needed to drive the Germans out of an established Brazilian base. If the Army Air Corps had enough tactical strength to accomplish this mission, it would also have more than enough to carry out other hemisphere defense missions (though of course not simultaneously), "such as meeting a possible Japanese attempt to land in Hawaii, or a threat based on the Maritime Provinces" of Canada. These calculations led to the conclusion that hemisphere defense needs could be met by increasing the planned combat strength of the Air Corps from 3,300 to 3,741 airplanes .75

During the fall and winter of 1939-40, the Army continued to work on plans for mobilization and for the deployment of ground and air forces to guard the hemisphere against military attack. Though not yet authorized, the Army based its plans on the assumption that it would have a Regular enlisted strength of 280,000 at its disposal when an emergency arose. The detailed plans provided for three expeditionary or "task" forces: No. 1, a reinforced infantry division to be available for dispatch to the Natal area of Brazil; No. 2, a similar division for the west coast of South America; and No. 3, a reinforced corps (one cavalry and three infantry divisions) as a general expeditionary force reserve. Supporting air units were earmarked to accompany each of the forces. The three forces combined would require only 57,000 enlisted strength for both ground and air units, since the units concerned were to be at peace strength and not at war strength. A war situation that required the full application of RAINBOW 1 and its subordinate Army


and Navy plans would lead to a general mobilization under the Protective Mobilization Plan, which would provide a 1,000,000-man army. The 1939 plans called for a general mobilization only if Great Britain and France were defeated .76

For the same reasons that had slowed down the tempo of Army plans and preparations, American public and Congressional opinion became increasingly complacent toward the dangers inherent in the world situation. As the apparent military stalemate in western Europe continued into 1940, Congress was in no mood to approve further increases in military strength beyond those authorized in 1939. Indeed, General Marshall feared that the Army might be required to curtail its expansion considerably short of the planned "National Defense" strength of 280,000; similarly, he believed that there was no hope of securing a projected increase of the National Guard to an enlisted strength of 320,000, and in March 1940 felt obliged to shelve the proposal for obtaining an authorization of this move.77  What the Army could do was mold a larger proportion of its existing strength into ground units ready for action. New divisions were organized, including the nuclei of two armored divisions. This reorganization progressed to the point where the Army could plan for corps and army maneuvers in the spring of 1940 involving the assembly of 70,000 troops. But the Chief of Staff was even more interested in obtaining Congressional authorization for purchase of reserves of guns and ammunition for the larger Army that a worsening of the war situation would certainly require. During February 1940, in testimony before the House Appropriations Committee, he said: "If Europe blazes in the late spring or summer, we must put our house in order before the sparks reach the Western Hemisphere . . . {and} prepare ourselves against the possibility of chaotic world conditions."78  These were prophetic words in the light of events soon to occur.



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