If someone makes a practical argument for torture, are you under any intellectual obligation to respond with a practical argument against? There are plenty of those, but as Lindsay Beyerstein puts it:
It’s sort of like writing rape-prevention posts about how you shouldn’t rape people, because it’s not going to be as much fun as you think, and you might drive your victim into the arms of radical feminists, etc. It seems either obscene or otiose to explain to would-be rapists why rape is a poor means to their ends.
There [is] something morally distasteful about being patient or reasonable with rapists. Same with torturers. I suppose that if I thought I could convince people not to rape with good arguments, I would try. Maybe the mistake is assuming that torturers are motivated by rationality any more than rapists.