On December 4, 1917, Wilson appeared before Congress to deliver the 1917 State of the Union Address. In it, he requested a declaration of war against Austria-Hungary and stated such a declaration to be necessary to "clear away with a thorough hand all impediments to success." Wilson went on to charge that Austria-Hungary was "the vassal of the German government" and was acting as the "instrument of another nation." However, Wilson's real impetus for seeking a declaration of war against was the situation in Italy. American military planners believed that it might soon be necessary to deploy American forces to shore up Italian defenses against robust Austrian gains. In response to Wilson's address, Henry D. Flood introduced House Joint Resolution 169, a declaration of war, which was referred to the House Committee on Foreign Affairs for consideration. The committee issued a report stating that the "state of war which this declaration declares to exist actually has been a fact for many months" and unanimously recommended adoption of the resolution. The report went on to charge that in September 1915, Konstantin Dumba, the Austro-Hungarian ambassador to the United States, had masterminded a scheme of industrial sabotage aimed at American manufacturing and that on April 4, 1917 the crew of an unflagged submarine boarded and then sank the American schooner SV Marguerite in the Mediterranean and that the nationality of the submarine was suspected Austrian since "Austrian was the language spoken by the officer of the submarine."
Enactment
On December 7 House Joint Resolution 169 was adopted by the House of Representatives in a vote of 365-1, and by the Senate in a vote of 74-0. The president signed the declaration later that day.
Debate
, who had earlier voted against the declaration of war against Germany, voted in favor of the declaration of war against Austria-Hungary, stating that "the vote we are now to cast is not a vote on a declaration of war. If it were, I should vote against it. This is a vote on a mere technicality in the prosecution of a war already declared." The sole vote of opposition in the House came from Meyer London, a Socialist representative from New York. On the floor of the House, London declared that he hated "professions of loyalty" but that he believed "I am as deeply in love with the United States as any man who can trace his ancestry to the Mayflower." However, London said that his constituents opposed war and that he preferred the United States to adopt an arms embargo against Europe, the same rationale that he had given for opposing the declaration of war against Germany. He was roundly denounced on the floor of the House. In the Senate, Robert M. La Follette did not vote on the resolution since he had departed the chamber to return to his office and to prepare an amendment to the declaration that would guarantee that the United States would not participate in the postwar dismemberment of Austria. While La Follette was out of the chamber, the vote was called. La Follette later said that he would have voted against the resolution in the form that it was passed. ''; news of the war declaration was overshadowed by the devastating Halifax Explosion, the third-largest non-nuclear explosion in history.
Text of declaration
International reactions
Aftermath
In autumn 1918, the imperial government collapsed, and on October 18, Stephan Burián von Rajecz, acting on behalf of the remnants of the state organs, sued for peace. The US Senate declined to ratify the Treaty of Saint-Germain-en-Laye and the Treaty of Trianon, which established peace between the Allied powers and Austria-Hungary and resulted in the formal dissolution of the Austro-Hungarian Empire. As a result, the state of war between the United States and a nonexistent Austria-Hungary continued, albeit without active hostilities, until it was officially terminated by the U.S.–Austrian Peace Treaty and the U.S.–Hungarian Peace Treaty, which were signed by Austria-Hungary's successor states: Austria and Hungary. The sinking of the SV Marguerite has been credited to the SM U-35, a German U-boat.
