6.8SPC_Dump,
I don't think your points sound crazy at all, you hit some of the challenges we face, perhaps I am more of a cynic. We have provided military stability in Europe since WW2, but equally important was the economic provisions of the Marshall Plan and Bretton Woods, more so IMHO than any "charitable benevolence". The Soviets were a real threat. The deal we made with Western Europe and Japan was okay, first we will defend you, (NATO), second we will rebuild your economies and basically ensure your economic success by committing to buying your goods. A constant foreign budget deficit isn't abnormal with this model since the US consumer is contributing to stability abroad.
Now times change, and empires fade, I'm not saying America is immune to this, I agree Third World economies are developing and will take a bigger piece of the pie, but militarily or economically where is the challenger?
Militarily our geography and the US Navy's control of the seas makes us a tough target. We can retain the role of a spoiling state, we just need to maintain the balance of power status quo abroad. Nuclear Proliferation is the biggest challenge.
Economically, where is this successor? In the 1980's we thought it was Japan, they had bad loans and haven't done anything but maintain employment for over a decade, they are also running out of population. The Europeans, maybe if they could ever put aside their cultural differences and unite, but they are as evidenced by the current Greek Euro debt crisis as fragmented as they ever where. They have a common currency (for now) and defense pact (for now), but they don't share a common government or fate. America got past that in 1865. You live in NY, I live in CA while we may argue the Dodgers vs Yankees, we share a congruency in being Americans first and a shared fate, when I hear of the bombing attempt in Times Square I am fired up. To the Germans, the Greeks are lazy irresponsible slackers, and the Greeks don't want to be under Germany's thumb. Okay so maybe the Chinese or the Indians, both countries here have a chance to develop, but both are cursed with overpopulation and dangerously widening income gap, I think China will implode because of this.
Domestically , I don't mean to be pie in the sky, I agree the standard of living will likely go down in the near term with unemployment here. We certainly face tough economic challenges going forward I think it gets much worse before it gets better, and we need to address regulations for OTC derivatives, this healthcare time bomb and the Mexican border violence are real serious issues, but we will endure and move forward.