On the day after 9/11, foreign newspapers ran headlines announcing "We Are All Americans Now." Though the sentiment was not new, it was also not quite the same as when Henry Luce announced in 1941, the inauguration of what he called "the American Century," during which the US was to raise all men "from the level of the beasts to what the Psalmist calls a little lower than angels."
When America suddenly emerged as a global power in the postwar...