I couldn't agree more with Matt Yglesias on this one. When you believe every opposing force is Hitler-like, logically, preemptive war is the most attractive option every time. The reality is that every opposing force is not Hitler-like and diplomacy does work in many cases. 

I'm also sick and tired of people equating diplomacy and appeasement. They are not the same thing. That being said, this equation has kept the Neocons in power for a long time, so I don't think it will go away any time soon. As long as there is an "enemy" of the United States out there, there will be politicians scaring people into voting for them.