President Woodrow Wilson, on April 2nd, 1917, spoke before a special joint session of Congress, and presented his argument for why the United States should abandon neutrality and opt for war with Germany and its allies.
After war broke out in Europe in August, 1914, the United States government, with Wilson in the White House, implemented and sought to maintain a policy of neutrality in military affairs, in hopes of keeping America out of the war. Although the government took no side in the conflict, it did allow trade with all parties – which, over time, resulted in a sharp decline in exports to Germany and a marked increase in sales to England and France. Given the geography of the Atlantic Ocean and British willingness to outspend Germany, American merchants, farmers, and companies profited from the war, while Germany became increasingly blocked – financially and otherwise – from taking part in ‘free trade’ with the United States.
Although incidents such as the sinking of the Lusitania, in May 1915, increased friction between the United States government and that of Germany, it was not until early 1917, and Germany’s decision to begin a campaign of unrestricted submarine warfare – that is, they were going to sink any ships they thought were carrying supplies to their enemies – that Wilson decided that the seeming benefits of neutrality on paper did not equal the reality of that policy in action, as American ships, sailors, and interests were put at significantly greater risk. That, and Germany’s backroom dealings with Mexico in early 1917, pushed Wilson to decide on a change in policy.
Accordingly, Wilson asked that Congress opt to declare war on Germany, and as part of his argument sought to frame such a war as one for reasons greater than simply those of American self-interest, but of global moral necessity.
Read Wilson’s speech in full here, and consider his argument, the situation at the time, Wilson’s handling of American policy as related to the war to that point, and the enduring question of when do American interests demand American intervention.