"Q What's your definition of the word ‘torture'?
"THE PRESIDENT: Of what?
"Q The word ‘torture.' What's your definition?
"THE PRESIDENT: That's defined in U.S. law, and we don't torture.
"Q Can you give me your version of it, sir?
"THE PRESIDENT: Whatever the law says."
See 18USC Sec.2340 ("[c] the threat of imminent death;") for the U.S. criminal code definition of torture. The U.S. has signed agreements with 50 countries to immunize Americans from prosecution for war crimes before the International Criminal Court at The Hague. It has suspended $47 million in aid from those countries which have refused to sign such agreements.
I find it really disturbing that Judge Mukasey, the nominee for Attorney General, was not willing to classify water boarding as torture, regardless of the possible legal repercussions against individual American who have tortured detainees. He apparently forgot that Congress gave agents immunity for acts of torture in the 2006 Military Commissions Act. In fact, all of the approved enhanced interrogation methods qualify as torture under the criminal code definition since they are "intended to inflict severe mental or physical pain or suffering" on a person within custody or control of another "acting under color of law". Parsing the word "severe" is neither justified by common sense or the plain meaning of the statute. The water board technique was regarded as torture at the turn of the last century when it was used in the Philippines against captured insurrectionists. President Teddy Roosevelt warned General Chaffee, "Great as the provocation has been...nothing can justify the use of torture or inhuman conduct of any kind on the part of the American Army." Roosevelt privately called the 'water cure', as it was known then, "an old Filipino method of mild torture." Apparently we have regressed beyond the 1920's to 1900 thanks to 'Dr. Yes', David Addington, Darth Dick and other unitary absolutists who were waiting for an excuse to become really despicable instead of just fringe.
Update: Raw Story reports that according to documents obtained by the ACLU from a 2003 FOIA suit, General Michael Dunlavey, in command of the Guantanamo gulag asked the Pentagon for permission to use torture on detainees. According to the General, Bush personally gave him"marching orders" to use torture and abusive treatment on detainees. The documents also show that former Secretary of Defense Donald Rumsfeld was personally involved in overseeing the degrading treatment of Mohammed Al Qahtani. This detainee was forced to parade naked in front of females on a dog leash and do tricks while wearing woman's underwear on his head. Silly but true. The Army at the time of the Abu Ghraib revelations in 2003 was aware of 62 other allegations of detainee abuse in Iraq and Afghanistan. [cartoon credit: Jim Morin