Sen. Rand Paul (R-Ky.) maintained on "The Real Story" that he supports a "strong and robust" military following his debate night clash with Sen. Marco Rubio (R-Fla.)

On Tuesday night, Paul criticized Rubio's proposed trillion dollars in new military spending as "not very conservative," but Rubio fired back that Paul is a "committed isolationist."

"I believe that the world is a safer and a better place when the United States is the strongest military power in the world," Rubio said.

Paul countered that it is not conservative to add a trillion-dollar expenditure to the federal government that you won't be able to pay for.

The senator explained this afternoon that Rubio also favors child tax credits that are not paid for and plagued by problems with fraud and improper payments.

Paul noted that an investigation into the tax credits found that $4 billion was spent on illegal immigrants. 

He reiterated that he is not advocating a weaker U.S. military, pointing out that Admiral Mike Mullen said that the biggest threat to national security is the out-of-control debt. 

"I think the [military] is the number-one priority of spending. We currently spend more than the next 10 countries combined. ... We should have national defense be a priority, but it doesn't mean a blank check. ... If Marco Rubio had his way, he would pile on so much new debt that we would be inundated," said Paul.

Watch the discussion with Gretchen Carlson above.

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