The USA is now at war with Germany. It will be some time before the Americans have an army ready to send to Europe, as their pre-war army was tiny and fit only for ineffectual invasions of Mexico. The USA is now working to expand its army but it will not be until 1918 or possibly later that it is has a trained force large enough to send to Europe.
At sea though the Americans are ready for action. The country has a sizeable navy and is keen to commit it to the war against the U-boats. The first flotilla of US Navy destroyers arrives in the southern Irish port of Queenstown today. From here it will take part in patrols against the German submarine menace.
US warship in Queenstown (Visit Cobh)