What contributions did americans make in europe?

Naval Strategy: The German's use of unrestricted submarine warfare had rought havoc on allied ships. The U.S. established the use of convoys to fight against the German u-boats American troops: the number of allied troops was beginning to dwindle. Many believed the U.S. troops could not make a difference. However, German and other Central Power troops were also decreasing in numbers. All either side of the war needed were more troops (not necessarily better troops) to tip the scales of victory in their favor. The U.S. offered more troops which caused their numbers to exceed what was left of the German army. American supplies: the Allied powers in Europe were beginning to run out of supplies (it was hard to get trade ships through the u-boat blockade). When America joined the war she brought with her food, weapons, ammunition, etc. that had been produced in large quantities in the U.S. (** This excessive industrial production leads to overproduction at the wars end and eventually the Great Depression for farmers especially**)

He advocated for a separation of powers of the government and the ones enforcing the law.

I'll go with that