Huntsman said his role will be to make certain that the candidates are talking seriously about fixing Washington, from spending to entitlement programs such as Social Security that many have declared off limits.
"If you're looking to cut a family budget or a business table, you put everything on the table. You don't automatically dismiss things as sacred cows," he said. "It's just not intellectually defensible. ... Any other approach would smack of politics. I don't think we can afford to do that."
Huntsman, who served three Republican administrations, said his time as envoy in Beijing for a Democratic president would not be the disqualifier some have predicted.
He cited Gen. David Petraeus, Obama's pick to lead the CIA, and outgoing Defense Secretary Bob Gates; their service dates to the George W. Bush administration.
"They are representing every American's interests," Huntsman said.
They are not, however, running for president against the man who put them in their current jobs.
"I'm surprised that we've gotten to a point where we don't put our country first and put our party first. ... Accepting an assignment from everyone's president during a time of war, during a time of economic hardship is putting your country first.
"I won't shy away from that," he said. "If someone wants to hold that against me, they can."
He said in the interview that he wasn't certain about his presidential ambitions before accepting the China post.
"Sometimes you don't see yourself the way other people do. It wasn't something that was a burning desire within, you know?"
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