Well, there were several things. One was that the industry itself built in Detroit was abandoning the city - taking factories elsewhere, the corporate headquarters elsewhere.

I want my books to last, to stand the test of time, and to do that I focus on the forces that shape the subject - the cultural and sociological geography - to capture them in a way that will explain them no matter what they are doing.

And all of the big shots of the car industry are there, strutting their stuff. And that year, they're feeling especially good because cars were selling more than ever before.

I said that I'm only there to write the truth, I'm not going to cover anything up, but I'll put everything in context and get as close to the truth of this person as I can.

And that John F. Kennedy uttered the first variation of "ask not what your country can do for you" in Detroit on Labor Day in 1960. So Detroit was really central to Democratic politics United States. Every Democratic candidate would start their fall campaigns in Cadillac Square.

It seemed that I could tell the whole story pretty powerfully in those 18 months between October of '62 and the spring of '64 when they were all at their peak. And yet you could see some of the shadows of Detroit's demise coming.

I discovered in writing the biography of Bill Clinton that it is actually easier to write a biography of someone who is dead. Although you can't interview them, you have a fuller perspective on their whole life after they're gone and people are more willing to talk about them.