Dave wrote:Germany was superior to France in population, industrial output, technical sophistication, and in military arts. It also directly bordered France.
The Treaty of Versailles had castrated Germany, they were limited to an army of 100,000 men and were not allowed to keep their submarines or large battleships, they just went back to the drawing board and started again. They built superiority, as superiority can be built in any field. Complacency is probably the single most major cause of military defeat in human history.
With the (arguable) exception of military arts, the exact opposite is true with respect to Britain and America. There is no common border (not counting Canada, a 10% version of America) and America was superior in manpower and industry.
And you think this superiority couldn't be beaten no matter what? Overconfidence in your own ability is what loses wars. The Germans thought defeating the Soviet Union would be a simple matter, and then Stalin rebounded and ended up at the gates of Berlin.
America would simply invade Canada (cutting off an important source of manpower and food), embargo the Entente (cutting off American supplies of food, industrial production, and loans), attack British possessions in the Caribbean and Pacific, and support the Kaiserliche Marine in the North Atlantic. The established powers you refer to, with the exception of the Russian Empire (which lost), all had less manpower than America so I don't know what you're talking about. The British Empire in total had significantly more manpower than America, but good luck attempting to impose conscription in India and Africa given that it wasn't even possible in Canada.
I think it's amusing how you think the US could overextend itself to this degree, the Japanese fell into the same trap in WWII.