I just came up with a hypothetical situation with my roommate which I rather liked. We agree on most things politically, with the MAJOR glaring exception being the Iraq war, which I was in favor of and he vehemently opposed. But here's the sitution:

You have an American Al Queda sympathizer with lots of resources. He has publically stated his support of 9/11 and Al Queda. He admitedly would commit a suicide attack if given the chance. He has not, however, broken any laws. He has never taken any steps to contact anyone that would help him commit a terrorist act or offered his help. He has no bombs, no ability to carry out the suicide bombing, yet. We also know that we cannot track everything he does. He has too many resources to be able to keep 100% watch on. What do we do?

His argument is that we can't do anything. In the absense of having broken any laws, we have to err on the side of caution and justice.

I'm not sure. I don't feel comfortable having a guy like that running around. My inclination is to lock him up and say, look dude, "I'm sorry, this ain't exactly fair, but I can't run the risk.

This is basically a debate between viewing terrorists as enemies(war) or criminals. I think pre-9/11 we mistakenly treated them as criminals.