Inside the White House there were always extreme amounts of doubt about whether they should be escalating in Afghanistan. In fact, most of the president's advisers said, "This is probably not going to work." A lot of people in the military said, "This is probably not going to work."

Johnny Apple, a New York Times correspondent, wrote a front-page story saying Afghanistan could be a quagmire and he was mocked and derided. What is certainly true is that all sorts of resources that would have been used in Afghanistan were diverted to Iraq. Would those resources have helped? Almost undoubtedly. Whether or not Afghanistan would be a peaceful nation-state had we not gone into Iraq I doubt. Afghanistan is going to be Afghanistan, no matter how hard we try to make it something else.

Afghanistan would have been difficult enough without Iraq. Iraq made it impossible. The argument that had we just focused on Afghanistan we'd now be okay is persuasive, but it omits the fact that we weren't supposed to get involved in nation-building in Afghanistan.In my new book, I open with a quote from Donald Rumsfeld. In October 2001, he said of Afghanistan: "It's not a quagmire." Ten years later there are 150,000 Western troops there.

Afghanistan would have been difficult enough without Iraq. Iraq made it impossible. The argument that had we just focused on Afghanistan we'd now be okay is persuasive, but it omits the fact that we weren't supposed to get involved in nation-building in Afghanistan.

Clearly the American military has been a force for good for the United States. There's a reason we have a standing military. But there's something to be said for having a much smaller military because then we wouldn't be tempted to get involved in things we shouldn't be getting involved in.

By the time of Andi Parhamovich death, I had already grown skeptical of the Iraq war. What her death made me realize was what the actual price was. Going through that kind of loss and seeing how devastating it was on her family and friends made me decide that I was only going to write about things that I really believed in. I'm not going to compromise on that.

I want to be the greatest investigative reporter of my generation.