What's wrong with torturing terrorists?

WASHINGTON - The Bush administration has a deliberate strategy of abusing terror suspects during interrogations, Human Rights Watch said Wednesday in its annual report on the treatment of people in more than 70 countries. The human rights group based its conclusions mostly on statements by senior administration officials in the past year, and said President Bush's reassurances that the United States does not torture suspects were deceptive and rang hollow.
First of all opinion of Human Rights Watch, George Soros being one of its main benefactors, is far from neutral; secondly - I don't see a reason why torturing terrorists is such a bad thing? Especially known terrorists, to me these people are sub-human, I think they should be tortured and executed on Al Jazeera if that will prevent future attacks, expose valuable intelligence, or send a message to their comrades-in-arms - since violence seems to be the only language these people understand. Oh, how I wish I could get my hands on those responsible for Beslan school attack.