The evidence for our nation’s downward spiral isn’t sufficient to rule out the very opposite possibility: that the United States will become, in purely geopolitical terms, even stronger in coming decades. The mistake we make is not so much overestimating our problems, but underestimating the problems of our potential rivals. We think we’re the only country with decline-and-fall issues.

I’ll wager that many of the toughest challenges for Americans in the future won’t be associated with our geopolitical decline, weakness or decrepitude. No: Our challenges will be the unimagined consequences of our many successes.