I've benefited greatly from studying many effective people from history. Among those who've influenced me the most are Ronald Reagan, Theodore Roosevelt, and Winston Churchill. Each of the three altered history; each was self-created to a great extent; and each was a great student of history and leadership.

If leadership is, fundamentally, about serving others, then any one person should be able to move between being a "leader" and a "follower."

My Army reserve service was in the 1990s. It was, more than anything else, an opportunity for me to express gratitude. My understanding of and admiration for the American armed forces is deeper, better informed as a result. I'm among those who believe that military or other citizen service should be an expected part of every American's life.

Curiously, for all the outpourings of scholarship on Theodore Roosevelt, no one had written a book focused directly on his leadership approach, working in large part from his own letters and other writings. That opportunity was open, and I was privileged to step in.

Ronald Reagan's career was so unusual, so unprecedented, that this would be very interesting to learn, to gain understanding of his way of looking at the world.

Theodore Roosevelt is among the most captivating of presidents in our time, but his administration is often underestimated. Roosevelt's successes in domestic and international affairs are so wide-ranging as to appear obvious or inevitable in retrospect.

In a time when our nation is engaged in multiple, long-term wars, it's critical that "the military" not become an abstraction to the vast majority of Americans who are not participants.