I'm guessing, that by your statement, you don't believe our international customs through Airports are any more secure now than they were before 9-11, is that correct?
Well if that's true, then your premise would be valid, because it's not like we had a huge "terrorist watch list" before 9-11.
But in theory, we do now have a huge terrorist watch list at our official airport entry points and hopefully also at our official Canadian and Mexician points of entry (official border crossing points). And if we do, it's possible that a good number of these terrorists or terrorist-wannabes couldn't make it through our official points of entry.
In addition to that, it's possible the terrorists don't want to risk being tracked if they come in via the official points of entry. Aren't we fingerprinting and photographing all foreigners who come in through airports now? Perhaps they are worried about that.
I know if I were going to try to get into Iraq to go pick off a few terrorists, I wouldn't announce myself through official channels. I'd go to a neighboring country and walk in through the desert (so to speak).
I think you're applying too much law-abiding and rational thought to the terrorist mindset. But that's just my opinion, of course.
He may not understand, they already did that once, hence much improved security. He also may not understand that trucks with unknown loads enter this country daily from Mexico. They actually find some of them in places like Ca, Arizona, and Texas with 150 illegals packed into them. I am confident, knowledge of these major security breeches are well known to the terrorist.
If I were a Mid Eastern terrorist, the last place I'd want to be is at an American airport, where everyone in the terminal would be gawking, and staring holes through you.