Reading recent Matt Yglesias posts on Tapped, I wonder if there's a Wheel of Regime Change located in the basement of some right-wing think tank. The game is to spin it and write an article about how we should invade the country whose name comes up. (Occasionally a writer spins it too many times, and has to write about all the countries.) While this may be fun, it is not the way to generate good advice on foreign policy.
Apparently, some basic points about the way invasions go are being widely missed. When you invade a country and remove the head bad guy, that doesn't mean you win. You just create a power vacuum which every other random thuglord in the country wants to fill. Al-Qaeda's influence rises, as they generally aren't looked on well by stable governments anywhere, and they grow unchecked in times of chaos. You also have to tangle with nationalistic/religious types who are suspicious of your motives and don't like being invaded. (Robert Pape, who knows more about suicide bombers than anybody, points out that these religious nationalists are the primary cause of suicide terrorism.) Lots of the guys playing for power will be just as bad as whoever you overthrew, if not worse. They will want to blow things up and shoot people -- sometimes you, sometimes civilians. In the process, there will be local outbreaks of anarchy. More civilians will die.