American entry into World War I

American entry into World War I came in April 1917, after 2 1/2 years of efforts by President Woodrow Wilson to keep the United States neutral.

Americans had no inkling that a war was approaching in 1914. Over 100,000 were caught unawares when the war started, having traveled to Europe for tourism, business or to visit relatives. Their repatriation was handled by Herbert Hoover, an American private citizen based in London. The U.S. government, under the firm control of President Woodrow Wilson, called for neutrality "in thought and deed." Apart from an Anglophile element supporting Britain, public opinion went along at first. Wilson kept the economy on a peacetime basis, and made no preparations or plans for the war. He insisted on keeping the army and navy on its small peacetime bases. Indeed, Washington refused even to study the lessons of military or economic mobilization that had been learned so painfully across the sea.

The most important indirect strategy used by the belligerents was the blockade: starve the enemy of food and the military machine will be crippled and perhaps the civilians will demand an end to the war. The Royal Navy successfully stopped the shipment of most war supplies and food to Germany. Neutral American ships that tried to trade with Germany (which international law clearly allowed), were seized or turned back. The strangulation came about very slowly, because Germany and its allies controlled extensive farmlands and raw materials, but it eventually worked because Germany and Austria took so many farmers into their armies. By 1918 the German cities were on the verge of starvation; the front-line soldiers were on short rations and were running out of essential supplies. The Allied blockade had done its job. The Germans also considered a blockade. "England wants to starve us," said Admiral Alfred von Tirpitz, the man who built the German fleet and who remained a key advisor to the Kaiser. "We can play the same game. We can bottle her up and destroy every ship that endeavors to break the blockade."^[1] Unable to challenge the more powerful Royal Navy on the surface, Tirpitz wanted to scare off merchant and passenger ships en route to Britain. He knew from his close reading of Captain Alfred Thayer Mahan that a blockade would not itself win the war. But he reasoned that since the island of Britain depended on imports of food, raw materials and manufactured goods, scaring off even half the ships would effectively undercut its long-term ability to maintain an army on the Western Front. While Germany only had nine long-range U-boats at the start of the war, it had ample shipyard capacity to build the hundreds that would be needed. The problem was that the U.S. demanded Germany respect international law, which protected neutral American ships on the high seas from seizure or sinking by either belligerent. (Other neutral nations made the same point; Berlin was probably more solicitous of Italy in than the US because Italy had an army.) Furthermore, Americans insisted that the drowning of innocent civilians was barbaric and grounds for a declaration of war. The British frequently violated America's neutral rights by seizing ships, but they did not drown anyone.^[2] As Wilson's top advisor, Colonel House commented, "The British have gone as far as they possibly could in violating neutral rights, though they have done it in the most courteous way." When Wilson exploded in protest at British violations of American neutrality, the British backed down (or the American ambassador, notoriously biased toward Britain, softened his chief's angry words.) German submarines torpedoed ships without warning, and some sailors and passengers drowned. Berlin explained that submarines were so vulnerable that they dare not surface near merchant ships that might be carrying guns, and anyway the subs were so small they could not rescue crews. Military "necessity" again.

Britain armed most of its merchant ships with medium calibre guns that could sink a submarine, making an above-water attacks too risky. In February, 1915, the U.S. sharply warned Germany about misuse of submarines but on May 7, the British passenger liner Lusitania was torpedoed with the loss of 1,198 civilians, including 128 Americans. The American outcry was far more intense than would accompany the deliberate shooting down or sabotage of a civilian airliner in the 1980s or 1990s, but not as sharp as the response to the 9-11 Attack in 2001. The Lusitania sinking was the event that decisively swung American opinion. Washington gave Berlin an ultimatum--never do that again! Berlin acquiesced, ordering its submarines to avoid passenger ships. But by January 1917 Generals Hindenburg and Ludendorff decided that unrestricted submarine blockade was the only way to break the stalemate on the Western Front. They demanded that Kaiser William II order unrestricted submarine warfare be resumed. Berlin knew that meant war with the United States, but they gambled that they could win before America's potential strength could be mobilized. They vastly exaggerated how many ships they could sink and how much that would weaken Britain; they did not figure out that convoys would defeat their efforts. They were correct in seeing that the United States was so weak militarily that it could not be a factor on the Western Front for more than a year. The civilian government in Berlin objected, but the Kaiser sided with the military (proving that Germany was indeed an undemocratic militaristic state.)^[3]

Wilson believed that peace would never come to a world that contained aggressive, powerful, non-democratic militaristic states. Peace required a world based on free democracies. There was never a possibility for compromise between these polar situations. America had to fight for democracy, or it would be fighting perpetually against ever-stronger evil enemies (stronger because they would gobble up weak neighbors whenever they could.) Was the American dedication to neutral rights and opposition to submarines sincere? In the 1920s and 1930s the world repeatedly condemned unrestricted submarine warfare. After Pearl Harbor in 1941, however, President Franklin Roosevelt, who held the key role as Assistant Secretary of the Navy throughout the first war, did not recognize any neutrality. He ordered his submarines to sink on sight all ships in Japanese waters, with no regard to passengers. (Indeed, thousands of American prisoners of war were drowned.) Despite this later reversal, in 1915-1917 Washington and the American people were dead serious about their opposition to unrestricted submarine attacks on neutral ships. They clearly told Germany they would fight for the principle.

A surprising factor in the development of American public opinion was how little the political parties became involved. They seemed fearful that discussion of war-related issues would distract the electorate from their tried-and-true platforms focused on economic issues. The Socialist party, which won 2% of the 1916 vote for Eugene V. Debs, blamed the war on capitalism and pledged total opposition. "A bayonet," it said, "was a weapon with a worker at each end." When war began, however half the Socialists supported it; the rest, led by Debs, became die-hard opponents.

Nationwide at all times the dominant voice was held by old-stock white Americans. The largest old-stock Protestant denominations (Methodist, Baptist, Presbyterian, Disciples of Christ, Congregational and some Lutheran groups) loudly denounced the war at first: it was God's punishment for sin. Their moralism was aggressively focused on banishing evils (like saloons) from the face of the earth through Prohibition, and if they could be shown that German militarism was a similar evil, they would throw enormous weight. Wilson, the intensely religious son of a prominent theologian, knew exactly how to harness that moralism in his attacks on the "Huns" who threatened civilization, and his calls for an almost religious crusade on behalf of peace.

Upwards of four-fifths of America's social, political, and economic leaders were of English or Scottish descent (usually Episcopalian or Presbyterian); they clearly wanted Britain to win, though at first not to the point of American entry. Magazine editors, newspaper reporters, book publishers, college professors, intellectuals, artists, and writers were overwhelmingly pro- British. Samuel Insull, one of Chicago's richest and most influential industrialists, had been born in England. He organized publicity, propaganda, and relief work, and assisted young men to join the Canadian army to go and fight.^[4] Chicago and the Midwest generally was isolationist and opposed to war, primarily because the large German and Scandinavian populations were strongly opposed to American entry. (Almost no one proposed the U.S. enter the war on Germany's side.)

The working class was relatively quiet, and tended to divide along ethnic lines; farmers generally ignored the war. A cosmopolitan group of upper and upper-middle class businessmen based in the largest cities took the lead in promoting military preparedness and in defining how far America could be pushed around before it would fight back.

American cities were polyglot concentrations of ethnic groups--in New York, Chicago, Detroit, and other great cities three-fourths or more of the voters were immigrants or sons of immigrants (women did not vote). Some British immigrants worked actively for intervention. London-born Samuel Insull, Chicago's leading industrialist, for example, enthusiastically provided money, propaganda, and means for volunteers to enter the British or Canadian armies. After US entry, Insull directed the Illinois State Council of Defense, with responsibility for organizing the state's mobilization. Immigrants from eastern Europe usually cared more about politics in their homeland than politics in the U.S. Slavic immigrants hoped that an Allied victory would bring independence for their homelands. The millions of German-Americans were ambiguous in their position. They called for neutrality, and spoke of the superiority of German culture. Increasingly, however, they spoke only to themselves, and by 1917 no one else listened.

The most effective opponents of the war were the Irish Catholics. They had little interest in the continent, but were adamant against helping the British Empire, because it continued to reject independence for Ireland. (The Easter Uprising in Dublin, 1916, was stamped out, its leaders hung.) The Irish-Americans dominated the Democratic party in most large cities, so Wilson had to take account of their views in his definition of the nation's goals. They did not prevent him from being hostile to Germany, but they did force him to keep his distance from Britain. Indeed, Irish pressure guaranteed that the US would not become a full-fledged ally of Britain, and would not be pledged to Britain's war aims, but would try to restructure the world in a liberal democratic fashion after the war was won.

By 1915, Americans were paying much more attention to the war. The sinking of the Lusitania was the eye-opener for most people regarding German brutality. That year, a strong "Preparedness" movement emerged. It argued that the United States needed to immediately build up strong naval and land forces for defensive purposes; an unspoken assumption was that America would fight sooner or later. General Leonard Wood (still on active duty after serving a term as Chief of Staff of the Army), ex-president Theodore Roosevelt, and former secretaries of war Elihu Root and Henry Stimson were the driving forces behind Preparedness, along with many of the nation's most prominent bankers, industrialists, lawyers and scions of prominent families. Indeed there emerged an "Atlanticist" foreign policy establishment, a group of influential Americans drawn primarily from upper-class lawyers, bankers, academics, and politicians of the Northeast, committed to a strand of Anglophile internationalism. Representative was Paul D. Cravath, one of New York's foremost corporation lawyers. For Cravath, in his mid-fifties when the war began, the conflict served as an epiphany, sparking an interest in international affairs that dominated his remaining career. Fiercely Anglophile, he strongly supported American intervention in the war and hoped that close Anglo-American cooperation would be the guiding principle of postwar international organization.^[5]

The Preparedness movement had a "realistic" philosophy of world affairs--they believed that economic strength and military muscle were more decisive than idealistic crusades focused on causes like democracy and national self determination. Emphasizing over and over the weak state of national defenses, they showed that America's 100,000-man Army even augmented by the 112,000 National Guardsmen, was outnumbered 20 to one by Germany's army, which was drawn from a smaller population. Reform to them meant UMT or "universal military service." They proposed a national service program under which the 600,000 men who turned 18 every year would be required to spend six months in military training, and afterwards be assigned to reserve units. The small regular army would primarily be a training agency.

Antimilitarists complained the plan would make America resemble Germany (which required two years' active duty). Advocates retorted that military "service" was an essential duty of citizenship, and that without the commonality provided by such service the nation would splinter into antagonistic ethnic groups. One spokesman promised that UMT would become "a real melting pot, under which the fire is hot enough to fuse the elements into one common mass of Americanism." Furthermore, they promised, the discipline and training would make for a better paid work force. The hostility to military service was so strong at the time it is difficult to imagine such a program winning approval; indeed, even in World War Two, when Stimson as Secretary of War proposed a similar program of universal peacetime service, he was defeated.^[6] Underscoring its commitment, the Preparedness movement set up and funded its own summer training camps (at Plattsburg, New York, and other sites) where 40,000 college alumni became physically fit, learned to march and shoot, and ultimately provided the cadre of a wartime officer corps.^[7]

Suggestions by labor unions that talented working class youth be invited to Plattsburg were ignored. The Preparedness movement was distant not only from the working classes but also from the middle class leadership of most of small town America. It had had little use for the National Guard, which is saw as politicized, localistic, poorly armed, ill trained, too inclined to idealistic crusading (as against Spain in 1898), and too lacking in understanding of world affairs. The National Guard on the other hand was securely rooted in state and local politics, with representation from a very broad cross section of American society. The Guard was one of the nation's few institutions that (in some northern states) accepted blacks on an equal footing.

The Democratic party saw the Preparedness movement as a threat. Roosevelt, Root and Wood were prospective Republican presidential candidates. More subtly, the Democrats were rooted in localism that appreciated the National Guard, and the voters were hostile to the rich and powerful in the first place. Working with the Democrats who controlled Congress, Wilson was able to sidetrack the Preparedness forces. Army and Navy leaders were forced to testify before Congress to the effect that the nation's military was in excellent shape.

In fact neither the Army nor Navy was in shape for war. The Navy had fine ships but Wilson had been using them to threaten Mexico, and the fleet's readiness had suffered. The crews of the "Texas" and the "New Mexico," the two newest and largest battleships, had never fired a gun, and the morale of the sailors was low. The Army and Navy air forces were tiny in size. Despite the flood of new weapons systems unveiled in the war in Europe, the Army was paying scant attention. For example, it was making no studies of trench warfare, poison gas or tanks, and was unfamiliar with the rapid evolution of air tactics. The Democrats in Congress tried to cut the military budget in 1915. The Preparedness movement effectively exploited the surge of outrage over the "Lusitania" in May, 1915, forcing the Democrats to promise some improvements to the military and naval forces. Wilson, less fearful of the Navy. embraced a long-term building program designed to make the fleet the equal of the Royal Navy by the mid 1920s. "Realism" was at work here; the admirals were Mahanians and they therefore wanted a surface fleet of heavy battleships second to none--that is, equal to Britain. The facts of submarine warfare (which necessitated destroyers, not battleships) and the possibilities of imminent war with Germany (or with Britain, for that matter), were simply ignored.

Wilson's program the army touched off a firestorm.^[8] Secretary of War Lindley Garrison adopted many of the proposals of the Preparedness leaders, especially their emphasis on a large federal reserves and abandonment of the National Guard. Garrison's proposals not only outraged the localistic politicians of both parties, they also offended a strongly held belief shared by the liberal wing of the Progressive movement. They felt that warfare always had a hidden economic motivation. Specifically, they warned the chief warmongers were New York bankers (like J. P. Morgan) with millions at risk, profiteering munition makers (like Bethlehem Steel, which made armor, and DuPont, which made powder) and unspecified industrialists searching for global markets to control. Antiwar critics blasted them. These selfish special interests were too powerful, especially, Senator LaFollette noted, in the conservative wing of the Republican Party. The only road to peace was disarmament, reiterated Bryan.

Garrison's plan unleashed the fiercest battle in peacetime history over the relationship of military planning to national goals. In peacetime, War Department arsenals and Navy yards manufactured nearly all munitions that lacked civilian uses, including warships, artillery, naval guns, and shells. Items available on the civilian market, such as food, horses, saddles, wagons, and uniforms were always purchased from civilian contractors. Armor plate (and after 1918, airplanes) were exceptions that have caused unremitting controversy for a century. After World War Two, the arsenals and Navy yards were much less important than giant civilian aircraft and electronic firms, which became the second half of the "military-industrial complex."  Peace leaders like Jane Addams of Hull House and David Starr Jordan of Stanford redoubled their efforts, and now turned their voices against the President because he was "sowing the seeds of militarism, raising up a military and naval caste." Many ministers, professors, farm spokesmen and labor union leaders joined in, with powerful support from a band of four dozen southern Democrats in Congress who took control of the House Military Affairs Committee. Wilson, in deep trouble, took his cause to the people in a major speaking tour in early 1916, a warmup for his reelection campaign that fall. Wilson seems to have won over the middle classes, but had little impact on the largely ethnic working classes and the deeply isolationist farmers. Congress still refused to budge, so Wilson replaced Garrison as Secretary of War with Newton Baker, the Democratic mayor of Cleveland and an outspoken opponent of preparedness. (Garrison's kept quiet, but felt Wilson was "a man of high ideals but no principles.") The upshot was a compromise passed in May 1916, as the war raged on and Berlin was debating whether America was so weak it could be ignored. The Army was to double in size to 11,300 officers and 208,000 men, with no reserves, and a National Guard that would be enlarged in five years to 440,000 men. Summer camps on the Plattsburg model were authorized for new officers, and the government was given $20 million to build a nitrate plant of its own. Preparedness supporters were downcast, the antiwar people were jubilant. America would now be too weak to go to war. Colonel Robert L. Bullard privately complained that "Both sides [Britain and Germany] treat us with scorn and contempt; our fool, smug conceit of superiority has been exploded in our faces and deservedly." The House gutted the naval plans as well, defeating a "big navy" plan by 189 to 183, and scuttling the battleships. The battle of Jutland (May 31/June 1, 1916) saw the main German fleet nearly sunk by the stronger British fleet. Only brilliant seamanship and luck allowed it to escape. Arguing this battle proved the validity of Mahanian doctrine, the navalists took control in the Senate, broke the House coalition, and authorized a rapid three-year buildup of all classes of warships. A new weapons system, naval aviation, received $3.5 million, and the government was authorized to build its own armor-plate factory. The very weakness of American military power encouraged Berlin to start its unrestricted submarine attacks in 1917. It knew this meant war with America, but it could discount the immediate risk because the US Army was negligible and the new warships would not be at sea until 1919 by which time the war would be over, with Germany victorious. The notion that armaments led to war was turned on its head: refusal to arm in 1916 led to war in 1917.

By 1916 a new factor was emerging--a sense of national self interest and nationalism. The unbelievable casualty figures were sobering--two vast battles caused over one million casualties each. Clearly this war would be a decisive episode in the history of the world. Every American effort to find a peaceful solution was frustrated. Henry Ford managed to make pacifism look ridiculous by sponsoring a private peace mission that accomplished nothing. German agents added a comic opera touch. The agent in charge of propaganda left his briefcase on the train, where an alert Secret Service agent snatched it up. Wilson let the newspapers publish the contents, which indicated a systematic effort by Berlin to subsidize friendly newspapers and block British purchases of war materials. Berlin's top espionage agent, debonnaire Fanz Rintelen von Kleist was spending millions to finance sabotage in Canada, stir up trouble between the US and Mexico and to incite labor strikes. The British were engaged in propaganda too, though not illegal espionage. But they did not get caught; Germany took the blame as Americans grew ever more worried about the vulnerability of a free society to subversion. Indeed, one of the main fears Americans of all stations had in 1916-1919 was that spies and saboteurs were everywhere. This sentiment played a major role in arousing fear of Germany, and suspicions regarding everyone of German descent who could not "prove" 100% loyalty.^[9]Americans felt an increasing need for a military that could command respect; as one editor put it, "The best thing about a large army and a strong navy is that they make it so much easier to say just what we want to say in our diplomatic correspondence." Berlin thus far had backed down and apologized when Washington was angry, thus boosting American self- confidence. America's rights and America's honor increasingly came into focus. The slogan "Peace" gave way to "Peace with Honor." The Army remained unpopular, however. A recruiter in Indianapolis noted that, "The people here do not take the right attitude towards army life as a career, and if a man joins from here he often tries to go out on the quiet." The Preparedness movement used its easy access to the mass media to demonstrate that the War Department had no plans, no equipment, little training, no reserves, a laughable National Guard, and a wholly inadequate organization for war. Motion pictures like "The Birth of a Nation" (1915) and "The Battle Cry of Peace" (1915) depicted invasions of the American homeland that demanded action.

The press at the time reported that the only thing the military was ready for was an enemy fleet attempting to seize New York harbor--at a time when the German battle fleet was penned up by the Royal Navy. Navy Secretary Josephus Daniels, a pacifistic journalist, had built up the educational resources of the Navy and made its War College in Newport an essential experience for would-be admirals. However, he alienated the officer corps with his moralistic reforms, (no wine in the officers' mess, no hazing at Annapolis, more chaplains and YMCAs). Ignoring the nation's strategic needs, and disdaining the advice of its experts, Daniels suspended meetings of the Joint Army and Navy Board for two years because it was giving unwelcome advice, chopped in half the General Board's recommendations for new ships, reduced the authority of officers in the Navy yards where ships were built and repaired, and ignored the administrative chaos in his department. Bradley Fiske, one the most innovative admirals in American naval history, in 1914 was Daniels' top aide; he recommended a reorganization that would prepare for war, but Daniels refused. Instead he replaced Fiske in 1915 and brought in for the new post of Chief of Naval Operations an unknown captain, William Benson. Chosen for his compliance, Benson proved a wily bureaucrat who was more interested in preparing for an eventual showdown with Britain than an immediate one with Germany. Daniels and Benson rejected .. Love 1:458, 483-4 March 1917: Benson told Sims he "would as soon fight the British as the Germans" proposals to send observers to Europe, leaving the Navy in the dark about the success of the German submarine campaign. Admiral William Sims charged after the war that in April, 1917, only ten percent of the Navy's warships were fully manned; the rest lacked 43% of their seamen. Light antisubmarine ships were few in number, as if Daniels had been unaware of the German submarine menace that had been the focus of foreign policy for two years. The Navy's only warfighting plan, the "Black Plan" assumed the Royal Navy did not exist and that German battleships were moving freely about the Atlantic and the Caribbean and threatening the Panama Canal. Daniels' tenure would have been even less successful save for the energetic efforts of Assistant Secretary Franklin D. Roosevelt, who effectively ran the Department.^[10]

In early 1917 Berlin forced the issue. The decision to try to sink every ship on the high seas was the immediate cause of American entry into the war. Five American merchant ships went down in March. If further evidence were needed, the German foreign minister, Arthur Zimmerman, approached Mexico for an alliance; Mexico would join Germany in a war and be rewarded with the return of lost territories in Texas, New Mexico and Arizona (but not California). Outraged public opinion now overwhelmingly supported Wilson when he asked Congress for a declaration of war on April 2, 1917. The United States had a moral responsibility to enter the war, he proclaimed, to make the world safe for democracy. The future of the world was being determined on the battlefield, and American national interest demanded a voice. Wilson's definition of the situation won wide acclaim, and, indeed, has shaped America's role in world and military affairs ever since. Wilson saw that if Germany would win, the consequences would be bad for the United States. Germany would dominated the continent and perhaps would gain control of the seas as well. Latin America could well have fallen under Berlin's control. The dream of spreading democracy, liberalism and independence would have been shattered. On the other hand, if the Allies had won without help, there was a danger they would carve up the world without regard to American commercial interests. They were already planning to use government subsidies, tariff walls, and controlled markets to counter the competition posed by American businessmen. The solution was a third route, a "peace without victory" Wilson said. He meant a peace shaped, if not totally dictated, by the United States. George H.W. Bush's rhetoric against Saddam Hussein in 1990-91 closely echoed Wilson in 1917.

The story of American entry into the war is a study in how public opinion changed radically in three years' time. In 1914 Americans thought the war was a dreadful mistake and were determined to stay out. By 1917 the same public felt just as strongly that going to war was both necessary and wise. Military leaders had little to say during this debate, and military considerations were seldom raised. The decisive questions dealt with morality and visions of the future. The prevailing attitude was that America possessed a superior moral position as the only great nation devoted to the principles of freedom and democracy. By staying aloof from the squabbles of reactionary empires, it could preserve those ideals-- sooner or later the rest of the world would come to appreciate and adopt them. In 1917 this very long-run program faced the severe danger that in the short run powerful forces adverse to democracy and freedom would triumph. Strong support for moralism came from religious leaders, women (led by Jane Addams), and from public figures like long-time Democratic leader William Jennings Bryan, the Secretary of State from 1913 to 1916. The most important moralist of all was President Woodrow Wilson--the man who dominated decision making so totally that the war has been correctly labelled "Wilson's War." (The closest comparison is George W. Bush as the driving force behind the war with Iraq in 2003.)

In 1917 Wilson, a Democrat, proved his political genius by winning the support of most of the moralists by proclaiming "a war to make the world safe for democracy." If they truly believed in their ideals, he explained, now was the time to fight. The question then became whether Americans would fight for what they deeply believed in, and the answer turned out to be a resounding "YES".

Some observers at the time, and since, alleged that beneath the veneer of moralism and idealism there surely must have been some sordid forces at work. Some suggested a conspiracy on the part of New York City bankers holding $3 billion of war loans to the Allies, or steel and chemical firms selling munitions to the Allies. This conspiracy interpretation was based not on evidence but on an a priori theory that wars are always caused by greedy businessmen. However, the interpretation was popular among left-wing Progressives (led by Senator Robert LaFollete of Wisconsin) and among the "agrarian" wing of the Democratic party--including the chairman of the tax-writing Ways and Means Committee of the House. He strenuously opposed war, but when it came rewrote the tax laws to make sure the rich paid the most. (In the 1930s neutrality laws were passed to prevent financial entanglements from dragging the nation into a war.) In the 1930s some journalists pointed to the British propaganda that played on exaggerated tales of German barbarism and appealed to the basically British cultural roots of most Americans. In 1916 Bryan thought that pro-British sentiment had distorted Wilson's policies, so he became the first Secretary of State ever to resign in protest.

The problem with these explanations is that they ignore the depth of American disgust with what Germany actually did, and the threat it represented to American ideals. They tell the story of Hamlet while leaving out the King. Americans set a standard for German behavior in terms of human decency, political philosophy, international law, and American national interest, and Germany flunked all the tests badly. Germany failed the human decency test because it invaded Belgium, subjecting a neutral country to the ravages of warfare simply because its territory offered a convenient invasion route. Furthermore, when the Schlieffen plan failed, the Germans did not withdraw. Belgium kept the public's sympathy as the Germans executed civilians, and English nurse Edith Cavell; Herbert Hoover led a private relief effort that won wide support. Compounding the Belgium atrocities were new weapons that Americans found repugnant, like poison gas and the aerial bombardment of innocent civilians. (Zeppelins dropped bombs on London.)

Above all, American repulsion at the Germans focused on their submarines which sank the Lusitania in 1915 and other passenger ships without warning. That appeared to Americans as a unacceptable challenge to the America's rights as a neutral country, and as an unforgivable affront to humanity. After repeated diplomatic protests, Germany agreed to stop it. But in 1917 the Germany military leadership decided that "military necessity" (i.e. a chance to win) dictated the unrestricted use of their submarines. The Kaiser gave the order knowing full well it meant war with the United States--a country that his advisors felt was enormously powerful economically but too weak militarily to make a difference. The political philosophy Americans believed in was a combination of democracy and individualized freedom of the sort exemplified in Britain and France. The alternative to their entry into the war was a world dominated by German political values, including imperialism, militarism, and the suppression of minorities--a guaranteed formula for more wars in the future. Americans wanted a world of peace and democracy; In 1917 they realized that they must fight Germany to achieve it. One stumbling block was that Czarist Russia--which almost as politically repugnant as Germany--was one of the Allies. When a liberal revolution overthrew the Czar in March 1917, this obstacle suddenly vanished. War increasingly became the only choice left.

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• Smith, Daniel. The Great Departure: The United States and World War I, 1914-1920 (1965)
• Sterba, Christopher M. Good Americans: Italian and Jewish Immigrants during the First World War. 2003. 288 pp. online edition
• Tucker, Robert W. Woodrow Wilson and the Great War: Reconsidering America's Neutrality, 1914-1917, (2007). 272 pp. ISBN: 978-0-8139-2629-2
• Unger, Nancy C. Fighting Bob La Follette: The Righteous Reformer (2000)
• Venzon, Anne ed. The United States in the First World War: An Encyclopedia (1995)
• Ward, Robert D. "The Origin and Activities of the National Security League, 1914–1919." Mississippi Valley Historical Review 47 (1960): 51–65. online at JSTOR
• Witcover, Jules. Black Tom: Imperial Germany's Secret War in America (1989)

• The Papers of Woodrow Wilson edited by Arthur S. Link complete in 69 vol, at major academic libraries. Annotated edition of all of WW's letters, speeches and writings plus many letters written to him
• Wilson, Woodrow. Why We Are at War (1917) six war messages to Congress, Jan- April 1917

This article incorporates material from the Citizendium article "American entry into World War I", which is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License but not under the GFDL.

• NY Times main headline, April 2, 1917, President Calls for War Declaration, Stronger Navy, New Army of 500,000 Men, Full Cooperation With Germany's Foes
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• Extensive essay on Woodrow Wilson and shorter essays on each member of his cabinet and First Lady from the Miller Center of Public Affairs
• President Wilson's War Address