In reality, defenders or critics of torture as an appropriate interrogation technique, generally rely on one of three assumptions:
Torture is (or is not) the most, and sometimes the only, way to get actionable information from a reluctant respondent.
Torture is (or is not) ethically or morally acceptable behavior.
Torture is (or is not) illegal.
The first of these, usually expressed as "torture works," is the one that our former vice-president has embraced as his best hope for historical redemption. His present claim is that a couple of selected "reports," when declassified will prove the worth of torture as an interrogation technique, and therefore justify its use. The problem with his position is that he not only needs to demonstrate its efficiency, he also needs to prove a negative, that it was the only efficient way to get the information. That is a high, and I suspect, impossible bar to clear.
The second assumption, that torture is morally and ethically unconscionable, does not lend itself to easy definition, though it is almost certainly the most emotionally potent. This has proved to be a special problem for many Republicans, who find themselves in the position of somehow sanctioning a behavior that intuitively they know to be abhorrent. The mushy "Oh well" dismissal by Peggy Noonan, the blustering inanity of Pat Buchanan, or the uncontained anger and frustration of Shepherd Smith, are all manifestations of a political perspective which has become incomprehensible.
The most coherent, and useful, assumption regarding torture is the question of its legality. The manfully attempted effort by Messrs. Bybee, Yoo, and Addington to declare torture legal is now the subject of well-deserved ridicule and scholarly evisceration. Glenn Greenwald (see here for a recent example) and Jonathan Turley (see here), between them, have compiled the alternative and compelling comprehensive argument that some of what was done in our name by the previous administration was torture, and that torture is illegal. And Progressives, unlike their Republican brethren, will hold those responsible for this stain on our national reputation to account, regardless of political affiliation or political inconvenience.