How did the US help in WWII officially and unofficially?

Help? Without the U.S the world would've been screwed. Britain was almost finished when we declared war on Germany. We invaded Normandy along with the British but it was mostly American troops, in vaded several pacific islands losing loads of men, and the big one dropping the atom bomb on Japan to end the war.The Russians got to have Berlin since the Nazis had to direct their attention to the advancing British and American forces to the West allowing the Russians to seize Berlin. We should've let the Nazis finish off the Russians, look at what those sneaky ******** plunged the world into, and look at them now! We won the war for the rest of the world.