One thing worse than an America that is too strong, the world will learn, is an America that is too weak.

People do not change when you tell them they should; they change when they tell themselves they must.

To call the American role in the world imperial was, for many who did so, a way of asserting that the United States was misusing its power beyond its borders and, in so doing, subverting its founding political principles within them.

While analogies are useful, however, they can also be misleading. They smuggle in assumptions that can be wrong.

Economic growth is necessary to keep the promise - enormously important to individual Americans - that each generation will have the opportunity to become more prosperous than the preceding one, the popular term for which is 'the American dream.

Certainly, protecting oppressed people, stopping ethnic conflict and promoting responsible governance are worthy goals. But none is as important for American security and prosperity as keeping the peace in the Middle East, Europe and East Asia.

The American political system is so porous, it's so open, it's so frustrating for those who are trying to make policy.