Oddly enough, WWII was our last constitutionally declared war. Incidentally, we conquered Japan and forced them into unconditional surrender. They are three generations removed from that era. You can drone on all you like about INCENTIVE, but it doesn't change history or fact.
They have less than 250K active personnel in their armed forces. They're woefully unprepared to do anything unilaterally for the foreseeable future. Your wet dreams of Imperial Japan aside, they have much to do before they're capable of doing anything independently.
You are the one ignoring history.
Never in the history of this world has an educated, wealthy country chosen submission rather than fighting for survival when faced with extinction.
I have no idea why you believe human nature will be any different than what history and common sense tells one.
And the US, a much much larger country, had only 358k active military in 1940, yet we won a war.
http://www.alternatewars.com/BBOW/Stats/US_Mil_Manpower_1789-1997.htmIt is called INCENTIVE, and the survival instinct is one of the most powerful of human instincts.