Foreign policy has never been Herman Cains strong suit. But his response in the Las Vegas debate on the possibility of exchanging a soldier for Guantanamo Bay prisoners can’t be good for the former Godfather’s Pizza CEO.

Former CEO of Godfather's Pizza Herman Cain participates in the slipped up on a question on hostages. (JOHN GURZINSKI/AFP/GETTY IMAGES)

“I could see myself authorizing that kind of transfer,” Cain told Wolf Blitzer Monday afternoon when asked if he would free all the prisoners in Guantanamo Bay in exchange for one American hostage. “I would make sure that I got all of the information, I got all of the input, considered all of the options. ... I could make that call if I had to.”

The question stemmed from Israel’s decision to free 1,027 Palestinian prisoners in a swap with the militant group Hamas for one captured soldier.

In the CNN debate later in the evening, Cain appeared to not remember the question in detail. “I don’t recall him [Blitzer] saying that it was al Qaeda-related,” he said. Blitzer had described an “al Qaeda or some other terrorist group.

“My policy would be we cannot negotiate with terrorists. That’s where we have to start as a fundamental principle,” Cain continued. “I would never agree to letting hostages in Guantanamo Bay go. That wasn’t the intent at all.”

After the debate, moderator Anderson Cooper again brought up the earlier exchange with Blitzer and pointed out that Cain had, in fact, said he was open to trading prisoners for hostages.

“I spoke in error,” Cain said. “Maybe I didn’t understand the question.” When the tape was replayed, Cain said, “I misspoke because I was moving so fast. I would not do that, I simply would not do that.”

At the same time, Cain said he could not judge Israel’s decision to trade prisoners with Hamas because he did not have all the facts.

Cain’s shift on the issue is not in itself so bad — former House Speaker Newt Gingrich (Ga.) and Texas Rep. Ron Paul actually came to his defense (in a way), pointing out that former president Ronald Reagan once traded arms for hostages.

But Cain’s inability to remember his own answer from a few hours prior — and his initial apparent misunderstanding of a fairly simple question — does not look good.