Revolutionary war? France literally went into debt to make America win, Spain and the Dutch were also fighting as well, America would have lost if it wasn't for that, In the Civil War you got a point, although America did have a massive advantage over the weaker CSA, but you have a point still, that was America, and the end of World War II, the nuclear research was done by both British and American researchers, Britain gave America all of it's data on nuclear science, then America decided to not give the completed nuclear bomb blueprints to the UK even when the UK did half the research