Even though Lyndon Johnson's presidency was in many ways scarred forever by the war in Vietnam, and destroyed in a lot of ways, he - as a character - was even larger than his presidency. Being able to get to know him well, that firsthand relationship with this large character, I think is what drew me to writing books about presidents.

An adult friend of Lincoln's: "Life was to him a school.

(from John Hay's diary) “The President never appeared to better advantage in the world,” Hay proudly noted in his diary. “Though He knows how immense is the danger to himself from the unreasoning anger of that committee, he never cringed to them for an instant. He stood where he thought he was right and crushed them with his candid logic.

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

I think that's still what the American Dream means: that with perseverance, with hard work, you can become something, that the classes won't prevent you from becoming, that there's a movement up that ladder with hard work.

One of the important qualities that I think is often overlooked is just energy. It's vitality, and sort of a life force that some people have and others don't. Probably that is connected to a love of whatever it is that they're doing. Another quality that I think is central is confidence. Again, some people are more blessed with that than others.

Sometimes people will find things that are wrong. Sometimes they will even find an approach that you took wrong. If you think you took the right approach, then you just absorb the criticism, but you don't change your mind.