United States

There was no possibility of conflict between Germany and the United States so long as the former confined its warfare to the continent of Europe; a new situation full of potential danger arose, however, when the German authorities decided to use their new weapon, the submarine, to challenge British control of the seas. The German admiralty announced in February 1915 that all Allied vessels would be torpedoed without warning in a broad area and that even neutral vessels were not safe. Wilson replied at once that he would hold Germany to “strict accountability” (a conventional diplomatic term) if submarines destroyed American ships and lives without warning. The Germans soon gave broad guarantees concerning American ships, and their safety against illegal submarine attacks was not an issue between the two countries before 1917.

An issue much more fraught with danger was the safety of Americans traveling and working on Allied ships. A German submarine sank the unarmed British liner Lusitania" class="md-crosslink">Lusitania without warning on May 7, 1915, killing, among others, 128 Americans. Wilson at first appealed to the Germans on broad grounds of humanity to abandon submarine warfare, but in the subsequent negotiations he narrowed the issue to one of safety for unarmed passenger liners against violent underseas attack. Momentary resolution came when a submarine sank the unarmed British liner Arabic in August. Wilson warned that he would break diplomatic relations if such attacks continued, and the Germans grudgingly promised not to attack unarmed passenger ships without warning. The controversy escalated to a more dangerous level when a submarine torpedoed the packet steamer Sussex in the English Channel with heavy loss of life in March 1916. In an ultimatum to Berlin, Wilson threatened to break diplomatic relations if the Germans did not cease attacking liners and merchantmen without warning; once again the Germans capitulated, but they threatened to resume unrestricted submarine warfare if the United States failed to force the British to observe international law in their blockade practices.

The New York Herald reporting the sinking of the Lusitania, a British ocean liner, by a German submarine on May 7, 1915.Hulton Archive/Getty Images

The Allies complicated the submarine controversy in late 1915 by arming many of their liners and merchantmen sailing to American ports. Wilson tried to arrange a compromise by which the Allies would disarm their ships in return for a German promise not to sink them without warning. When the British rejected the proposal, the president gave the impression that he would hold Germany accountable for American lives lost on armed ships, setting off a rebellion in Congress and the near passage of resolutions forbidding American citizens to travel on armed ships. Actually, the president had no intention of permitting armed ships to become a serious issue; their status was never a subject of serious controversy between the United States and Germany.

Arming for war

Meanwhile, the increasingly perilous state of relations with Germany had prompted Wilson, in December 1915, to call for a considerable expansion in the country’s armed forces. A violent controversy over preparedness ensued, both in Congress and in the country at large. The army legislation of 1916 was a compromise, with Wilson obtaining only a modest increase in the army and a strengthening of the National Guard, but the Naval Appropriations Act of 1916 provided for more ships than the administration had requested.

The United States enters the Great War

Wilson’s most passionate desire, aside from avoiding belligerency, was to bring an end to the war through his personal mediation. He sent Colonel House to Europe in early 1915 to explore the possibilities of peace and again early in 1916 to press for a plan of Anglo-American cooperation for peace. The British refused to cooperate, and the president, more than ever eager to avoid a final confrontation with Germany on the submarine issue, decided to press forward with independent mediation. He was by this time also angered by the intensification of British blockade practices and convinced that both sides were fighting for world domination and spoils. On December 18, 1916, Wilson asked the belligerents to state the terms upon which they would be willing to make peace. Soon afterward, in secret, high-level negotiations, he appealed to Britain and Germany to hold an early peace conference under his leadership.

Break with Germany