CBS:

"We used it against these three detainees because of the circumstances at the time," Hayden said during a Senate hearing. "There was the belief that additional catastrophic attacks against the homeland were inevitable. And we had limited knowledge about al Qaeda and its workings. Those two realities have changed."

Hayden said that Khalid Sheik Mohammed - the purported mastermind of the 9/11 terrorist attacks on the United States - and Abu Zubayda and Abd al-Rahim al-Nashiri were subject to the harsh interrogations in 2002 and 2003. Waterboarding is an interrogation technique that critics call torture. Read on...