"I want his policies that I believe take us in the wrong direction to fail," Thompson told Roberts on CNN's American Morning.
"If he takes us down the road of tripling our national debt in ten years and making us vulnerable to higher interest rates and higher inflation, and things of that nature, I want all those policies not to succeed," he said.
Thompson, who made the rising cost of entitlement spending a focus of his 2008 presidential run, said he'd be happy to help Obama overhaul those programs.
"If he wants to do that, I will join with him. I'll do everything I can to make him succeed with regard to that because that's the whole ball game in terms of our fiscal future in this country," said the former Tennessee senator.