Richard N. Haass is president of the Council on Foreign Relations, this country’s preeminent independent, nonpartisan institution devoted to thinking about America’s role in the world. Haass was director of policy planning for the Department of State, where he was a principal advisor to Secretary of State Colin Powell from 2001 to 2003, as well as special assistant to President George H.W. Bush and senior director on the staff of the National Security Council from 1989 to 1993.

In an exclusive excerpt from his new book, Colin Powell's former adviser explains why neither of them resigned despite reservations about the Iraq invasion.