The other day, I wrote that to argue about the effectiveness of torture is to concede that this argument is relevant to the debate over whether or not we should do it.  Conor Friedersdorf disagrees:

That's incorrect. All one concedes by arguing about the effectiveness of torture is that people worth persuading believe -- mistakenly or not -- that utility is a relevant factor. I happen to think that every American who exerts influence on his or her government is a person worth persuading. A mistaken policy like torture is least likely to happen if as large a plurality of citizens as possible think that it's a bad idea, for whatever reason.

In theory this is true.  In practice, people who argue opportunistically don't fare well much outside debate tournaments.

In real life, when someone argues that we shouldn't torture, and also that torture doesn't work, and also that torture leads to socialism, their arguments lose force, particularly if they are forced to  admit that one of their arguments was wrong.  That's because the people you're arguing with care whether torture works, and you don't.  They are interested in the factual question of what interrogation techniques produce usable information.  You are interested in proving that torture doesn't work as a way of forcing them towards your moral conclusion.  They will rightly suspect that your investigation of the factual question is not likely to be of a high quality.  And indeed, that is what I find in these arguments:  people wildly overstating an at best modest case that torture rarely produces all that much usable intelligence.

Once someone has been through that wringer with you, and you say, okay, well, you're right, I didn't really care whether torture worked, and my arguments weren't very good, but Look!  Another argument against torture! . . . well, you've proven that you'll say anything to try to herd them towards your moral conclusion.  And also that you're willing to waste phenomenal amounts of time making irrelevant arguments.  They will be angry with you, and not particularly inclined to listen to yet another argument.

Acting as if you're persuadable when you're not often seems like an initially attractive way to sucker your ideological opponents into an easy victory.  But I've rarely seen it work in practice.  Think of the ridiculous debates over breast cancer and abortion, or the rear-guard action against climate-change science.  When they conceded, people didn't say, "well, okay, science is hard, it was a mistake, could have happened to anyone."  Those arguments severely weakened the credibility of those movements on their issues, and they now have to fight the perception that they are mendacious ideologues who will say anything, no matter how stupid, to win.