<Li> No point in ordering reparations, because so much damage had been caused to all belligerents </Li> <P> At the outbreak of the war, the United States pursued a policy of non-intervention, avoiding conflict while trying to broker a peace . When the German U-boat U-20 sank the British liner RMS Lusitania on 7 May 1915 with 128 Americans among the dead, President Woodrow Wilson insisted that "America is too proud to fight" but demanded an end to attacks on passenger ships . Germany complied . Wilson unsuccessfully tried to mediate a settlement . However, he also repeatedly warned that the United States would not tolerate unrestricted submarine warfare, in violation of international law . Former president Theodore Roosevelt denounced German acts as "piracy". Wilson was narrowly reelected in 1916 as his supporters emphasized "he kept us out of war". </P> <P> In January 1917, Germany resumed unrestricted submarine warfare, realizing it would mean American entry . The German Foreign Minister, in the Zimmermann Telegram, invited Mexico to join the war as Germany's ally against the United States . In return, the Germans would finance Mexico's war and help it recover the territories of Texas, New Mexico, and Arizona . The United Kingdom intercepted the message and presented it to the U.S. embassy in the U.K. From there it made its way to President Wilson who released the Zimmermann note to the public, and Americans saw it as casus belli . Wilson called on antiwar elements to end all wars, by winning this one and eliminating militarism from the globe . He argued that the war was so important that the U.S. had to have a voice in the peace conference . After the sinking of seven U.S. merchant ships by submarines and the publication of the Zimmermann telegram, Wilson called for war on Germany, which the U.S. Congress declared on 6 April 1917 . </P> <P> The United States was never formally a member of the Allies but became a self - styled "Associated Power". The United States had a small army, but, after the passage of the Selective Service Act, it drafted 2.8 million men, and, by summer 1918, was sending 10,000 fresh soldiers to France every day . In 1917, the U.S. Congress granted U.S. citizenship to Puerto Ricans to allow them to be drafted to participate in World War I, as part of the Jones--Shafroth Act . If Germany believed it would be many more months before American soldiers would arrive and that their arrival could be stopped by U-boats, it had miscalculated . </P>

What was the major reason for united states entry into world war 1