We [the United States] are the world's only superpower right now, so everyone notices every bit of what we do or don't do.

I'm defining [presidential courage] pretty narrowly. It's not only taking a big political risk but it's also the risk that in the hindsight of history, people think it's wise.

Then you get to the last half of the 20th century, Americans are getting very skeptical about their leaders and their institutions, and another place that is affected is parties and conventions.

So the result was that as one approached a political convention for most of the 19th century and for most of the 20th century until the 1960's, part of the drama was the fact that you didn't know ultimately who was going to be the nominee at the end of that convention week.

First of all, there's no mention of political parties in the Constitution, so you begin American history with not only no political conventions but also no parties.

We cannot be spun, or at least we'd like to think that we cannot be. And the presidents who are trying to - too overtly to try to say, here is what you historians and what you later Americans should think of my presidency, 30 or 40 years later, they look silly.

The original thing that fascinated me most was why we expect leaders, and especially presidents, at times to destroy themselves - and that's a sign of being a good leader or a good president. We usually don't expect that of almost anyone else in any profession, in particular, in public life.