This may tip my hat, but I found one particular part of Obama's 100-day speech interesting on this topic. He retold the story of Churchill during World War II. England was being mercilessly bombed. It was horrible. And England had about 200 enemy combatants. However, instead of stooping to torture chose to take a long-term, moral approach by not allowing torture. His reasoning was that once taking a step like that a society could never go back. No matter what happened the rest of the war, there would be this long-term impact of choosing to treat people that way. He took the more difficult path.
Torture is easier. Is it worth it for the short-term or long-term?