The post-9/11 era has featured a continuing, heated debate over the question of whether there can ever be justification for using “enhanced interrogation” measures to obtain strategic intelligence from captured terrorists or enemy combatants. The measures in question include, among others: depriving a suspect of sleep; forcing a suspect to stand in uncomfortable positions for many hours at a time; forcing an incarcerated suspect to stand naked for extended periods in 50-degree temperatures; forcefully grabbing the shirt of a suspect and shaking him; issuing an open-handed slap designed to cause pain (though not injury) and fear in a suspect; and, most famously, subjecting a suspect to the technique known as waterboarding, which has been used by CIA agents on a small number of high-level al Qaeda operatives. (Click here and here for a detailed description of waterboarding and its effects.)

The George W. Bush administration assigned numerous lawyers to examine each of these enhanced interrogation procedures and determine whether any of them were so extreme or dangerous as to constitute torture. The attorneys concluded that none of the methods in question could be classified as torture. But critics of enhanced interrogation continue to contend that not only are such methods unacceptably cruel and inhumane, but that they are also unlikely to yield any information that can be considered reliable. After banning the practice of waterboarding in the first days of his presidency, for example, Barack Obama said:

“I am absolutely convinced [that this] was the right thing to do, not because there might not have been information that was yielded by these various detainees who were subjected to this treatment, but because we could have gotten this information in other ways, in ways that were consistent with our values, in ways that were consistent with who we are.”

The President's perspective was echoed by members of his administration at every level. Attorney General Eric Holder, for instance, condemned the Bush administration for having “authorized torture” and “needlessly abusive and unlawful practices” that “have diminished our standing in the world community and made us less, rather than more, safe.” On another occasion, Holder characterized enhanced interrogation as “cruel, inhuman and degrading.”

In April 2009, against the protests of former CIA director Michael Hayden, President Obama, reiterating his contention that enhanced interrogation techniques “did not make us safer,” publicly released a number of the legal memos in which Bush administration attorneys had explained why such methods should be deemed lawful. According to Hayden, Obama's action was a potentially disastrous move because it provided "our enemies in the midst of a war" with "very valuable information" about exactly what "are the outer limits that any American would ever go to in terms of interrogating an al Qaeda terrorist."

Also in the early months of his presidency, Obama indicated that his Justice Department might in fact seek to prosecute the Bush attorneys who had written the aforementioned memos. “I would say that that is going to be more of a decision for the Attorney General within the parameters of various laws,” said the President. Eventually the Obama administration announced that it would not pursue the Bush lawyers in court.

The CIA agents who had implemented the policies authorized in the legal memos, however, were not offered any such assurance. In August 2009, Attorney General Holder announced that "the information known to me warrants opening a preliminary review into whether federal laws were violated in connection with the interrogation of specific detainees at overseas locations." As of May 2011, the possibility of legal action against the agents still existed.

The question of the efficacy of enhanced interrogation techniques, however, has continued to be debated. There is strong evidence that such interrogations have been effective in eliciting valuable intelligence. For example, a May 30, 2005 Justice Department memo noted the following:

“[T]he CIA believes the intelligence acquired from these [enhanced] interrogations has been a key reason why al Qaeda has failed to launch a spectacular attack in the West since 11 September 2001.... In particular, the CIA believes that it would have been unable to obtain critical information from numerous detainees, including [Khalid Sheik Mohammed, a.k.a. 'KSM'] and Abu Zubaydah, without these enhanced techniques.... Before the CIA used enhanced techniques ... KSM resisted giving any answers to questions about future attacks, simply noting, 'Soon you will find out.' [Once the techniques were applied], interrogations have led to specific, actionable intelligence, as well as a general increase in the amount of intelligence regarding al Qaeda and its affiliates.”

"[…] Interrogations of [Abu] Zubaydah—again, once enhanced techniques were employed—furnished detailed information regarding al Qaeda's organizational structure, key operatives, and modus operandi and identified KSM as the mastermind of the September 11 attacks.... Zubaydah and KSM also supplied important information about al-Zarqawi and his network [in Iraq].”

When Abu Zubaydeh began to reveal information as a result of the waterboarding, he explained that he and his fellow al Qaeda operatives were obligated to resist only until they could no longer do so, at which point it became permissible for them to cooperate with interrogators. Indeed he advised his interrogators: "Do this for all the brothers."

Of the thousands of unlawful combatants captured by the U.S., fewer than 35 were subjected to any enhanced techniques. Waterboarding in particular was used against an even smaller number of suspects. The amount of information yielded by such efforts, however, was immense. According to former CIA Director Michael Hayden, as of 2006, fully half of the government's knowledge about the structure and activities of al Qaeda had been learned via enhanced interrogation.

The value of enhanced interrogation was demonstrated yet again in the sequence of events that ultimately enabled the U.S. to hunt down and kill Osama bin Laden. A key development in the search for the elusive terror leader occurred in 2007, when two Guantanamo Bay detainees—Khalid Shaikh Mohammed and Abu Faraj al-Libbi—were shipped to an “extraordinary rendition” site in Eastern Europe where they were waterboarded. As a direct result of that waterboarding, these men provided U.S. officials with the nom de guerre of one of bin Laden's most trusted personal couriers. The informants indicated that the courier in question might be living with, and protecting, bin Laden. Proceeding from that tip, U.S. intelligence officials painstakingly set out to locate the courier. In August 2010 they finally succeeded in tracing him to a three-story residence in Abbottabad, Pakistan. Further surveillance suggested that bin Laden himself was also likely to be living there.
 Late on the night of May 1, 2011, forty U.S. Navy SEALS raided the house and indeed found bin Laden therein and killed him.

While taking credit for the terror leader's death, President Obama remained steadfast in his opposition to waterboarding and other forms of enhanced interrogation. When CBS News reporter Mark Knoller asked White House Press Secretary Jay Carney whether, in the wake of bin Laden's killing, “there has been any change in President Obama’s opposition to so-called enhanced interrogation techniques,” Carney replied: “No change whatsoever.”