Exactly. You should also raise your guard whenever someone is trying to convince you that reality never presents you with hard choices: "So I never have to weigh my aversion to torture against my aversion to the loss of thousands of lives? Hooray!"
Whereas whatever the hell people want to talk about with 24-esque do-or-die scenario begs dozens if not hundreds of follow up questions, all of which have one thing in common: they've nothing to do with torture as conducted by the US to date, which has taken place over the course of years in a systemic fashion in which no assurances that the people we're torturing are even involved with "the enemy" have been able to be given.
But that's a different argument entirely from "this tool can never work."
I think we have to accept that sometimes we are, at least temporarily, operating according to ideas we can't fully justify. We have to be willing to be temporarily wrong or misguided.