Good leadership requires you to surround yourself with people of diverse perspectives who can disagree with you without fear of retaliation.

You can be enormously effective for a period of time, because it's almost like there's an engine in you that needs to keep going, and you have a greater drive than other people - who may be more happy and balanced in life - because you have to keep going out and proving yourself over and over again.

The one thing that John Kennedy did, above all else, was to energize young people to feel that they wanted to give something to their country. I just hope, for young people of this generation, that they'll experience that feeling once again, that by working on large goals, they can do something more than their own individual ambition.

People will love him (Theodore Roosevelt) for the enemies he has made.

When you are an historian, there's probably nothing that matters more than to be recognized by your colleagues in your own profession. I was lucky enough to win the Pulitzer Prize for History. I had to give a talk right after that to some young people. The most important thing to tell them, I think, is that you can't ever know that it's going to turn out that way.

Though [Abraham Lincoln] never would travel to Europe, he went with Shakespeare's kings to Merry England; he went with Lord Byron poetry to Spain and Portugal. Literature allowed him to transcend his surroundings.

I'd like to think that what my style of writing is, is an attempt not so much to judge the characters that I'm writing about, to expose them, to label them, to stereotype them, but instead to make them come alive for the reader with all their strengths and their flaws intact.