For starters, he's resurrected the whole profiling canard just as recent events made it irrelevant; the dirty bomber wasn't middle eastern, he was hispanic.. and a citizen as well. I mean, do Glenn (and the others) think that the minds behind Al Qaeda are stupid? While it's true that many Muslims are middle eastern (and probably many "Islamists", focusing solely on them will simply mean that Al Qaeda will use operatives that don't look middle eastern, and that honestly isn't that hard. Sure, they might be able to find a greater number of possible bombers in the Middle East, but it's hardly exclusive, and the administration will simply have ensured that thousands of middle eastern men will be delayed and yet real operatives will easily slip through.
The other point that I have to disagree with Glenn's column is below:
Wars are won by destroying the enemy, not by playing defense. Now we've got a huge, multi-multi-billion-dollar government department dedicated to playing defense. (And one that, being a bureaucracy, won't ever go away, even if the war is won).
Many bureaucratic empires will be built, many budgets will be enhanced (the administration says that this reorganization won't lead to additional spending, but nobody believes that) and many meetings will be held. Will any of this do as much to protect us from terrorism as a daisy-cutter on Saddam Hussein, or the neutralization of Saudi Arabia's campaign to spread Islamic fundamentalism around the world? I doubt it.
Ok, first, this is a war against terrorism, not the Middle East. (At least, not yet). Eliminate Saddam and Saudi Arabia and you've still got terrorists, but you've managed to ensure the enmity of even more of the middle east. While Bin Laden may have started off as a Saudi national (as well as many of the 9/11 bombers), there's no reason to believe that Al Qaeda requires the support of either of these countries to function, either politically or financially.
Second, a question is raised by the idea of "attacking the enemy"... attack whom, exactly? This is a war against a concept, and I have never quite understand how exactly it can be won. Even if you reduced Iraq and Saudi Arabia to radioactive glass, there are many other nations that can play host to terrorists (even without their knowledge) and many more terrorists that will be missed by these attacks. It would probably even make things worse, because every third world country that might or might not have terrorist camps will wonder whether they're next. Even if every current terrorist were rounded up and shot, it still wouldn't kill the idea of attacking civilians in order to demoralize and psychologically traumatize the perceived enemy; as long as there are conflicts between nations and inside nations, terrorism will continue to exist. Terrorism is a tactic or a strategy... and I've never even heard of a successful attempt to contain either. At best you can deter it (as with nuclear attacks) or make it cost more than it's worth (which is meaningless to those with nothing to lose).
I'm not saying that Bush should simply give up, but there needs to be a hell of a lot more thought put into this than simply "let's/let's not eliminate Saddam and the House of Saud". There are questions at the center of this, questions that people aren't (including Glenn) aren't asking.