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Likely presidential candidate Rick Santorum on Wednesday said he was trying to discuss U.S. policy and not Sen. John McCain's personal experience when he said a day earlier that the former POW doesn't understand the effectiveness of waterboarding and other tough interrogation techniques.

Santorum referenced McCain, who spent more than five years in a North Vietnamese prison, during a radio interview in which he disagreed with McCain's claims last week that waterboarding Al Qaeda's No. 3 leader, Khalid Sheikh Mohammed, did not provide information that led to Usama bin Laden's compound in Pakistan.

"Everything I've read shows that we would not have gotten this information as to who this man was if it had not been gotten information from people who were subject to enhanced interrogation," Santorum told host Hugh Hewitt. "And so this idea that we didn't ask that question while Khalid Sheikh Mohammed was being waterboarded, he (McCain) doesn't understand how enhanced interrogation works."

Shortly afterward, a spokeswoman for McCain said his office would not dignify Santorum's comments with a response. But the remarks drew a stinging retort from former longtime McCain adviser Mark Salter. Salter, who most recently advised McCain during his unsuccessful 2008 presidential campaign, fired back via Facebook.

"Ron Paul may be the wackiest candidate in the GOP field. But for pure, blind stupidity, nobody beats Santorum. In my 20 years in the Senate, I never met a dumber member, which he reminded me of today," Salter wrote.

McCain addressed the interrogation issue last week amid a charged debate on Capitol Hill over how important the enhanced techniques used during the prior administration were in pinpointing bin Laden's location.

McCain said he asked CIA Director Leon Panetta for the facts, and that the hunt for bin Laden did not begin with fresh information from Mohammed. In fact, the name of bin Laden's courier, Abu Ahmed al-Kuwaiti, came from a detainee held in another country.

"Not only did the use of enhanced interrogation techniques on Khalid Sheikh Mohammed not provide us with key leads on bin Laden's courier, Abu Ahmed, it actually produced false and misleading information," McCain said.

But Santorum insisted that waterboarding played a role in compelling Mohammed to eventually provide information.

"I mean, you break somebody, and after they're broken, they become cooperative. And that's when we got this information. And one thing led to another, and led to another, and that's how we ended up with bin Laden," said Santorum.

He added: "Maybe McCain has better information than I do, but from what I've seen, it seems pretty clear that but for these cooperative witnesses who were cooperative as a result of enhanced interrogations, we would not have gotten bin Laden."

Santorum said Wednesday that he still disagrees with McCain's view that the interrogation techniques were unsuccessful but he wasn't trying to belittle his sacrifice.

"For anyone to infer my disagreement with Senator McCain's policy position lessens my respect for his service to our country and all he had to endure is outrageous and unfortunate," he said.

The Associated Press contributed to this report.