"To show that [he] can."
Paul Krugman on the torture issue:
So why is the Bush administration so determined to torture people?
To show that it can.
The central drive of the Bush administration — more fundamental than any particular policy — has been the effort to eliminate all limits on the president's power. Torture, I believe, appeals to the president and the vice president precisely because it's a violation of both law and tradition. By making an illegal and immoral practice a key element of U.S. policy, they're asserting their right to do whatever they claim is necessary.
...
The fact is that for all his talk of being a "war president," Mr. Bush has been conspicuously unwilling to ask Americans to make sacrifices on behalf of the cause — even when, in the days after 9/11, the nation longed to be called to a higher purpose. His admirers looked at him and thought they saw Winston Churchill. But instead of offering us blood, toil, tears and sweat, he told us to go shopping and promised tax cuts.
Only now, five years after 9/11, has Mr. Bush finally found some things he wants us to sacrifice. And those things turn out to be our principles and our self-respect.