On the subject of US torture, Andrew Sullivan is far more eloquent than I. Among many articles he's posted on the subject, this one may be the best summary. Within it is a key paragraph:
Looked at from a distance, the Bush administration wanted to do two things at once: to declare to the world that freedom is on the march, and human rights are coming to the world with American help, while simultaneously declaring to captives that the US has no interest in the law, human rights, accountability, transparency or humanity. They wanted to give hope to all the oppressed of the planet, while surgically banishing all hope from the prisoners they captured and tortured. And the only way they could pull this off is by the total secrecy they constructed and defended. So we had a public government respectful of the rule of law, and a secret government whose main goal was persuading terror suspects that there was no rule of law at all. It is hard to convey just how dangerous this was and is.
We know the harm torture has done to our standing in the world. Other than unproven assertions, most of which have been contradicted by people at the center of it, we have no evidence that it helped in any way.
Many conservatives are horrified that the Obama administration has released the torture memos, and they pooh-pooh the idea that the techniques described even are torture (Heck, even Jenny Craig tortures: yes, it was used as justification!) Once again we see how certain issues that ought not have any political preference at all (among them: age of the Earth, creationism, climate change), seem to divide us along party lines. Given the undeniable truths about what it has and has not accomplished, I'm happy to be in the party that rejects torture.