Listen Otto, if USA was neutral and did not trade to either allies or axis, then the allied nations would have been screwed. Why? who supplied the Russians with technology, tanks, and guns? USA. Who helped feed the British when all their forms of economy were nearly destroyed? the USA. Britain held out because the Germans did not believe they could beat Britian by an Amphibious Assault. so they just wanted the British to surrender after continuous bombardments and starvation. a "seige." if britain had surrendered then and their, the whole entire west AND african front would have attacked Russia. and not just through poland, now with the British navy out of the war, the Germans would have been free to land ANYWHERE on russian borders along waterways. The Germans in africa would have attacked from southern Russia. So Virtually, Russia would be fighting about a 4 front war. Dont forget Japan would have been on the east and south east borders of russia. So if Britain fell, the battle for europe would be over, and all of Europe, Russia, Asia(most of it at least) and parts of africa would be speaking German/Japanese. Japan and Germany would have possibly duked it out, but I really doubt it because both nations would be far too busy trying to keep their newly conquered regions German or Japanese. And thats all if the British didnt survive the German onslaught. The United States would have never entered Europe had they not have a Foothold to stand on in europe. thats what Britain was.
Also, otto, i give the russians much kudos for their spyrings. without those spyrings throughout europe, you would have been screwed.