"Fiasco: The American Military Adventure in Iraq (Hardcover)"
http://www.amazon.com/Fiasco-America...182887-2240923
Whether for or against the war, check out the commentary on the book under "Making a fiasco" - interesting stuff.
I haven't read the book but it doesn't take a rocket scientist to see many things have gone wrong after the initial invasion / regime overthrow. This book seems very well researched into what's gone wrong.
"A Savage War of Peace: Algeria 1954-1962"
http://www.amazon.com/Savage-War-Pea...e=UTF8&s=books
This book is apparently being read by a lot of people even though it's not about Iraq. It's being read because the parallels are strong. It's about France's disastrous war in Algeria.