If you disagree then find a military and historic example for an empire with similar military superiority falling from grace in a decade. I cant think of one and ive been reading military history for 30 years. There might be one but the over whelming majority (if not all) last 100s of years and take at least 50 to decay. The thing that seems to stop most of them are world wars. The certainly dont fall form grace when the rest of the world is much weaker, its just never happened that way. So why are we predicting it today? The Americans will have robots running around the battlefield like Terminator in 10 years, the concept of remote wars where you dont actually send many troops is about to come into play? Will Americans stomach for waging war and their high handed morality become even more dominant if they cut their casualties by 80%? How about when they introduce nanobot swarms in 15 years time?
Seriously our children will laugh at us as comical for our naivety. IMO people also underestimate the lengths that they will go to stay at the top. History tells us that empires fight very hard to survive (thats why the last 100s of years) they do eventually fall but not now ?