This article at the Boston Globe discusses analysis of America’s so-called cruise to empire. I liked this conclusion particularly (though I don’t agree with it entirely; I don’t think disinterest is necessarily a vice and certainly not unique to the States.):
For many years, Americans have resisted any expensive and long-lasting involvement with countries whose ways of life are thoroughly unfamiliar. We resist an imperial role for America not because we are humanitarians and internationalists but because we are stingy with our government and lack genuine interest in the rest of the world. Our best defenses against empire, as it turns out, lie not in our virtues but in our vices.