1. While the Mafia was evil, it was not based on a central tenant of destroying our great country. Islam is. Big difference.
2. I personally have little sympathy for your friend. Why not? Because he is offended by our need to stop the insanity called Islam. I am sorry his people have decided to follow that path. Big time bummer of a situation to be in. But it is a truth that is slapping us in the face. Do you have a better solution? I feel this way because I know of no better solution.
A better solution: exactly what we're doing now: retribution, terrible and sure. Preventing a determined terrorist is nearly impossible; they'll find a way to a target, if they want to bad enough. Look at Israel-- they do everything you suggest. And they're getting the crap bombed out of them. Their relative peace was when Netenyahu was Prime Minister -- and he told Arafat he'd hold him personally responsible if there were any terrorist incidents. Suprise, suprise: there weren't any until Barak was PM. Or, to quote The Godfather: "If there's one thing history has taught us, its that you can get close to anyone." Perfect security is impossible.
Thus, security must rest on the fact that the Amerian response to terrorist threats will be terrible, swift, and sure. And we're doing that. Bin Laden's either dead, or he doesn't dare show his face. Saddam's hiding or dead too. That's done more to neutralize our enemies than our pathetic attempts of profiling security could ever do.