Point taken, and to an extent I agree
However, I think you know quite well what would happen to those individuals that did. It's not as cut and dry as 'hey come hide your bombs in my house' is it? Most members of these groups aren't the sort of people your average civvy wants to get on the wrong side of.
I personally believe that the only way to defeat terrorist groups is by changing the public opinion of those that sympathise or support them.
In a perverse kind of way the IRA was defeated by 9/11, bombs just did not seem such a glamourous thing after that, world opinion was against them and hey presto! That, along with the Madrid bombings also had a profound effect on ETA.
I think the Muslim world seems to be becoming increasingly divided by these issues. There is a divide. Most Muslims find terrorism as abhorrent as anyone else, but there has been an increase in global sympathy towards some groups. However, Al Qaida, from my experience are becomming more and more distanced from the mainstream Islam. Or maybe I should say most normal Muslims abhor terrorism and want to distance themselves from it.
Problem is, I honestly think, Israels actions of late have set things back years, if not decades.