In the immediate wake of the Tucson shootings, there's a lot of talk about how irresponsible, heated political rhetoric inflamed things to the point where this nutjob was driven to lash out. The logic behind that is beyond laughable, but it's still taking hold. Hell, one lawmaker who ought to know better -- Representative Bob Brady (D-PA) plans to introduce a bill to outlaw the use of "crosshairs" in political advertising.

The usage of violent, combat-related, warlike metaphors for politics is age-old and omnipresent. It's a key element of our discussion and conduct of politics. Hell,von Clausewitz famously said "war is not merely a political act, but also a political instrument, a continuation of political relations, a carrying out of the same by other means."

The use of warlike language and metaphors is an essential part of politics -- and I think generally, that is a good thing. It serves several purposes.

First, it acts as a catharsis for the participants. By channeling their energies into words and phrases and metaphors of war, they manage to vent their energies in verbal fashion -- and not into deeds.

Second, it gives us a chance to identify those who take things a bit too far. For example, now-former (thank heavens) Representative Alan Grayson (D-FL), a flaming whacko whose fiery rhetoric made him an embarrassment to pretty much everyone -- and a champion to some nuts. Or, on the other end of the spectrum, Pat Buchanan, who has mastered the art of running right up to the edge of declaring himself an anti-Semitic Nazi apologist, but not quite crossing the line.

Years ago, I coined a phrase for such things -- AEWIs, or Asshole Early Warning Indicators. These are the words and phrases that let you instantly determine that someone isn't worth your time in debating or even taking seriously. Racial and other epithets fall into this category, and lately I've added "teabagger" to the list.

The frothing idiots do us all a great service (in spite of themselves). They self-identify themselves, so we can keep an eye on them. And they tend to set off the truly dangerous ones, most often before they can cause serious harm.

But as we learned to our sorrow in Tucson, we will always have the crazies. And the saddest part about this one is that there were plenty of warning signs -- those who knew him were terrified of him, he was known to the police, and yet no one took the final step in stopping him from carrying out his heinous deeds of last Saturday.

To ban the use of certain aspects of heated language would not only be antithetical to the First Amendment, not only utterly meaningless, but in the long run harmful to the goal of making our politics less violent. Because banning the words merely means that the ideas behind them will grow and fester, instead of being purged.