I went out to cover the wars in Iraq and Afghanistan fundamentally [in Buzzing at the Sill] because I was interested in war as a notion and in experiencing it. I was interested in history and how societies form. I was interested in the recent history of what had provoked these wars. So when I finally got out there, I was really seeing the wars through the American perspective, much more than through being embedded with American soldiers and Marines.

At first Disco Night wasn't meant to be a book, although I'm always thinking about that in the back of my mind. It started off as a series of exploratory road trips that I was doing with Christian Hansen, who I dedicated the book to.

[The Middle East conflict ] just kind of ran its course for me. For a long time I could justify doing it to myself, no matter how irrational it was. It was important to me and my work. And I just don't feel it in the same way any more. When it comes up and it's important to me, I'll do it, but more out of sense of duty than desire - which used to be a big part of it.

I realized how little I knew about my own country. I had grown up in the suburbs and, after college, I moved out of the country, so I didn't really know the place well. When I started following soldiers and their families back home, it provoked a lot of the questions about who we are as a nation, questions I realized couldn't be explored through the more limited framework of looking at the military at war and at home.

What I was doing for those assignments wasn't always directly tied to what I was doing for myself, but it gave me the space to photograph. I started getting assignments that dealt with my own interests and made some pictures in that direction.

I think a lot of the work I've done and a lot of the work I'm going to do in the future still ties to 9/11 and the fallout from it.

Nothing is over until there's something more decisive than your own thoughts.