This topic is quite interesting and pretty controversial too.
Actually,yesterday was the International Day in Support of Torture Victims.Nice timing with the thread.
Anyway,on the torture issue,it could get very exaggerated,I found a lot of interesting stuff on that:
The evidence below shows that Bush, Cheney, Rumsfeld and Gonzales are guilty of violating "Federal Torture Act" Title 18 United States Code, Section 113C, the UN Torture Convention and the Geneva Convention by ordering and condoning the use of torture. Many prisoners have died as a result. Also, false information provided under torture was used to help justify the Iraq War with disastrous consequences.January 2002 - Ibn al-Shaykh al-Libi was secretly handed to Egypt and tortured. Al-Libi told his interrogators that Iraq was training Al Qaeda how to use explosives and chemical weapons. Bush used this "intelligence" as part of his justification to invade Iraq. In 2004 Al-Libi said he had fabricated these claims to escape the pain of torture.
Source
John Yoo, author of the infamous legal memo justifying Presidential powers to torture US captives around the world says president Bush can legally torture children:
Cassel: If the president deems that he's got to torture somebody, including by
crushing the testicles of the person's child, there is no law that can stop him?
Yoo: No treaty
Cassel: Also no law by Congress -- that is what you wrote in the August 2002 memo...
Yoo: I think it depends on why the President thinks he needs to do that.
Source
Also source
More on torture and its efficiency:
Here and
here
This is what waterboarding's like:

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