Why won containment work with Iraq?
Containment in and of itself doesn’t work against terrorist states. That’s because not only is it very easy for nations to hide their involvement in particular terrorist plots (ex: who was responsible for sending out the anthrax laced letters?), but the terrorist groups themselves are difficult to control. So simply threatening to retaliate for terrorist attacks sponsored by other nations is not an effective strategy. As an illustration of that, keep in mind that Afghanistan was completely “contained” on 9/11/2001.