From the Independent:
"In a further embarrassment for Mr Bush yesterday, Malcolm Nance, an advisor on terrorism to the US departments of Homeland Security, Special Operations and Intelligence, publicly denounced the practice. He revealed that waterboarding is used in training at the US Navy's Survival, Evasion, Resistance and Escape School in San Diego, and claimed to have witnessed and supervised "hundreds" of waterboarding exercises. Although these last only a few minutes and take place under medical supervision, he concluded that "waterboarding is a torture technique – period".
The practice involves strapping the person being interrogated on to a board as pints of water are forced into his lungs through a cloth covering his face while the victim's mouth is forced open. Its effect, according to Mr Nance, is a process of slow-motion suffocation.
Typically, a victim goes into hysterics on the board as water fills his lungs. "How much the victim is to drown," Mr Nance wrote in an article for the Small Wars Journal, "depends on the desired result and the obstinacy of the subject.
"A team doctor watches the quantity of water that is ingested and for the physiological signs which show when the drowning effect goes from painful psychological experience to horrific, suffocating punishment, to the final death spiral. For the uninitiated, it is horrifying to watch."
The CIA director Michael Hayden has tried to defuse the controversy. He claims that, since 2002, aggressive interrogation methods in which a prisoner believes he is about to die have been used on only about 30 of the 100 al-Qai'da suspects being held by the US. Meanwhile, a CIA official told The New York Times waterboarding had only been used three times. The Bush administration has suggested that the interrogation of al-Qai'da's second-in-command, Khalid Sheikh Mohammed, was a success thanks to the technique, and used this to justify continued aggressive interrogations of suspects in secret CIA prisons.
While US media reports typically state that waterboarding involves "simulated drowning", Mr Nance explained that "since the lungs are actually filling with water", there is nothing simulated about it. "Waterboarding," he said, "is slow-motion suffocation with enough time to contemplate the inevitability of blackout and expiration. When done right, it is controlled death."
Mr Nance said US troops were trained to withstand waterboarding, watched by a doctor, a psychologist, an interrogator and a backup team. "When performed with even moderate intensity over an extended time on an unsuspecting prisoner – it is torture, without doubt," he added. "Most people cannot stand to watch a high-intensity, kinetic interrogation. One has to overcome basic human decency to endure watching or causing the effects. The brutality would force you into a personal moral dilemma between humanity and hatred. It would leave you to question the meaning of what it is to be an American."