Sometimes a war is justified, and coming to the aid of an ally getting invaded is a damn good justification.
Especially if that ally is simply asking for more hardware and not asking for feet on the ground.
Edit: Fixed the link, it was broken for some reason though it worked earlier today. IDK this mirror should work though
20,000 American Nazis held a rally in Madison Square Garden. Facism was quite popular in the United States all the way til WW2 (and continued to be for 83 years afterwards).