In The Icarus Syndrome, Peter Beinart analyzes a century's worth of ill-fated American military adventures. (Reviews, April 5)

Your crowning example of American hubris is the Iraq War. What fueled that hubris?

The Iraq War was the product of a decade and a half of enormous American military, economic, and ideological success: American military victories, starting with Panama in 1989 and running through the early stages of the Afghan war in 2002; the economic boom; the global wave of democratization and market deregulation of the 1980s and 1990s. The book's theme is that success leads to hubris. People who've seen everything go right lose their sense of fallibility.

You were for the Iraq War before you were against it. Did you share the hubris?

I think so. I wrote the book to try to understand why, on the eve of the Iraq War, I believed things that, in retrospect, were hubristic. The experience of having seen so many countries move from authoritarianism to democracy, often quite rapidly—sometimes, as with Panama, because of [American military] intervention—made me optimistic. ...