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Marco Rubio hit Ted Cruz on foreign policy Sunday, calling him an isolationist

Rubio cited Cruz's votes against budget bills and for a program that limited government data collection

(CNN) —  

Marco Rubio says he isn’t buying Ted Cruz’s tough talk on national security.

The Florida senator hammered Cruz for opposing the U.S. government’s bulk phone data collection and voting against spending bills and defense authorization acts – suggesting Cruz’s voting record is that of an isolationist – in an interview on NBC’s “Meet the Press” Sunday.

“He talks tough on some of these issues. For example, he was going to carpet bomb ISIS. But the only budget he’s ever voted for in his time in the Senate is a budget that cut defense spending by more than Barack Obama proposes we cut it,” Rubio said of Cruz, his rival for the Republican presidential nomination.

“He voted against the Defense Authorization Act every year that it came up. And I assume that if he voted against it, he would veto it as president,” Rubio said.

“That’s the bill that funds our troops. Even the Iron Dome for Israel. So I guess my point is each time he’s had to choose between strong national defense and some of the isolationist tendencies in American politics, he seems to side with the isolationist,” Rubio said. “And this is an important issue to have a debate over. It’s not personal.”

The attack by Rubio previews a theme sure to show up in CNN’s Republican presidential debate Tuesday night in Las Vegas.

Cruz, who backed the USA Freedom Act, which ended the bulk metadata program, has argued U.S. intelligence agencies can work through the courts to get any surveillance approval they need – while Rubio says that jeopardizes U.S. security.

Cruz is known as a conservative brawler on Capitol Hill, using fights over budget bills to push for GOP-backed priorities like the repeal of President Barack Obama’s signature health care law. Those fights endeared Cruz to the right – but Rubio is now citing his votes to question Cruz’s national security credentials as Americans are increasingly focused on terrorism in the wake of attacks in Paris and California.

Still, Cruz has resisted Rubio’s characterizations of him as an isolationist.

Cruz has said he’s open to using U.S. military strength overseas – but told the Daily Caller earlier this year that he wants three preconditions.

“First, it should begin with a clearly stated objective at the outset. It should be directly tied to U.S. national security,” he said. “Second, we should use overwhelming force to that objective. We should not have rules of engagement that tie the hands of our soldiers and sailors and airmen and Marines.”

“Third, we should get the heck out,” Cruz said. “It is not the job of the U.S. military to engage in nation building to turn foreign countries into democratic utopias.”

In the “Meet the Press” interview, Rubio was also pressed about same-sex marriage.

He has always opposed same-sex marriage rights, but said he opposes a constitutional amendment to undo the Supreme Court’s ruling legalizing it everywhere because “that would be conceding that the current Constitution is somehow wrong and needs to be fixed. I don’t think the current Constitution gives the federal government the power to regulate marriage.”

Instead, he said, he’d rather appoint conservative justices who would reverse it.

“It is the current law. I don’t believe any case law is settled law,” Rubio said. “Any future Supreme Court can change it. And ultimately, I will appoint Supreme Court justices that will interpret the Constitution as originally constructed.”