The "neutrality" that the U.S. and allies instituted was more like a blockade. It was a dumb move on our parts. We should have been there to support, and protect the Republic. Had we done so, some historians believe Hitler wouldn't have had the guts to set his sights on conquering Europe, and the Soviet Union would have never come to be. I think he still would have made the attempt, but have been beaten long before he was, and the USSR wouldn't have existed.