But there is no equivalent word for murder when it comes to torture. It's always evil. Yet that's not our universal reaction. In movies and on TV, good men force evil men to give up information via methods no nicer than what the CIA is allegedly employing. If torture is a categorical evil, shouldn't we boo Jack Bauer on Fox's "24"? There's a reason we keep hearing about the ticking time bomb scenario in the torture debate: Is abuse justified in getting a prisoner to reveal the location of a bomb that would kill many when detonated? We understand that in such a situation, Americans would expect to be protected. That's why human-rights activists have tried to declare this scenario a red herring.

Sullivan complains that calling torture "aggressive interrogation techniques" doesn't make torture any better. Fair enough. But calling aggressive interrogation techniques "torture" when they're not doesn't make such techniques any worse.

Still, there is a danger that over time we may not be able to tell the difference.

Taboos are the glue of civilization because they define what is beyond the pale in ways mere reason cannot. A nation that frets about violating the rights of murder-plotters when the bomb is ticking is unlikely to violate the rights of decent citizens when the bomb is defused. I suspect this is what motivates so many human-rights activists to exaggerate the abuses and minimize their effectiveness. Slippery-slope arguments aren't as powerful as moral bullying. Still, their fears aren't unfounded. Once taboos have been broken, a chaotic search ensues for where to draw the new line, and that line, burdened with precedent and manufactured by politics, rarely holds as firmly as the last. But that is where history has brought us.

In the recent debate over torture, everybody decided to kick the can down the road on what torture is and isn't. This argument will be forced on us again, no matter how much we try to avoid it. We'll be sorry we didn't take the debate more seriously when we had the chance.