WILSON, Wyo. - Former Vice President Dick Cheney sought to bolster Mitt Romney's foreign policy credibility this evening during a high-dollar fundraiser at which he said the presumptive GOP nominee would be best suited to handle a terrorist attack as severe as 9/11.

"There is one other credential that I care a lot about, and I have learned over the years in all those administrations that there is always, sooner or later, a crisis that's totally unanticipated," said Cheney. "You can't plan on it. You don't know what it's going to be. You go through the campaigns and study the history books and talk to the experts. Sooner or later, there is going to be a big surprise - usually a very unpleasant one."

Cheney said that when he thinks about the kind of leader he wants to handle "life-and-death" decisions in that sort of situation, he thinks of Mitt Romney.

"Whether its 9/11 or the other kinds of difficulties or crises that arrive, they always do," said Cheney. "And that's when you really find out what kind of leader your president is. And I'm convinced that, in addition to all of these other qualifications that you all know about, when I think about the kind of individual I want in the Oval Office in that moment of crisis who has to make those key decisions, some of them life-and-death decisions, some of them decisions as the commander-in-chief who has the responsibility of sending our young men and women into harm's way - that man is Mitt Romney."

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The fundraiser, which was expected to raise more than $4 million, was co-hosted by former Vice President Cheney and his wife, Lynne, who will host a more exclusive dinner for the highest-dollar donors later this evening at their nearby home.

Held at a tony country club here where attendees were ushered between events in golf carts in the shadows of the Teton Mountains, Cheney's remarks came just more than a week before Romney will set off on the first foreign trip of his candidacy.

This is the first event at which Cheney and Romney have appeared together, and it was closed to television cameras.

The night was not devoid of humor. Cheney made a fleeting reference to the incident in which he accidentally shot a friend during a hunting trip in 2006.

"Dick is a man of great courage," said Cheney, referring to Dick Scarlett, another one of the co-hosts of the fundraiser who introduced the former vice president.

"I know that because he hunts with me," Cheney said.

Romney did not mention Bain Capital on a day that political news was dominated by questions regarding when exactly he left the private equity firm and whether that date was accurately reported.

Romney instead mocked President Obama for saying that his biggest mistake during his presidency was not telling more stories about his vision for America.

"He was asked what his biggest mistake was in his three-and-a-half years. I have a long list for him," said Romney, referring to an interview Obama did today with CBS News' Charlie Rose. "I mean, I just went through a few related to his domestic policy, but his foreign policy mistakes may be even longer lasting in their negative impact on the country.

"What was his answer as to his biggest mistake? Not telling stories to the American people about his vision," said Romney. "That was his biggest mistake. Oh really? Really? Look, look, he's out of touch, he's out of excuses, he's out of ideas and we've got to make sure in November we put him out of office."