A senior adviser to former American president George Bush says he's proud of the harsh interrogation techniques such as waterboarding that were used to get information from suspected terrorists.
Mr Bush's successor in the White House, Barack Obama, has barred the use of waterboarding after defining it as a form of torture.
But Karl Rove says it prevented further attacks against America and its allies and "kept the world safer than it was".
In a BBC interview he said waterboarding, which simulates drowning, should not be considered torture.
"I'm proud that we used techniques that broke the will of these terrorists and gave us valuable information that allowed us to foil plots such as flying aeroplanes into Heathrow and into London, bringing down aircraft over the Pacific, flying an aeroplane into the tallest building in Los Angeles and other plots," Mr Rove said.
"Yes, I'm proud that we kept the world safer than it was, by the use of these techniques. They're appropriate, they're in conformity with our international requirements and with US law."
US soldiers 'also subjected to it'
The practice was sanctioned in written memos by Bush administration lawyers in August 2002, though CIA head Michael Hayden told Congress in 2008 that it had only been used on three high-profile al-Qaeda detainees, and not for the past five years.
One of those detainees was Khalid Sheikh Mohammed, a key suspect in the 9/11 attacks.
Mr Rove also said US soldiers were subjected to waterboarding as a regular part of their training.