Rick Santorum Slams Rand Paul on ISIS: 'I'd Expect to Hear That From Maybe Bernie Sanders'

Paul has a "fundamental misunderstanding" of ISIS, Santorum said.

“I think that is just fundamentally a misunderstanding of the nature of the enemy we face,” Santorum said in an exclusive interview with ABC News’ Chief Anchor George Stephanopoulos.

“ISIS didn't come about because of ... the arms that America left behind. ISIS came about because they hate everything that we believe in and we stand for,” Santorum added. “I think the idea that we accept now that this tripe from the left that it’s our fault that ISIS exists -- go back to the thousand-year history of Muslim expansionism, and look at some of the horrible things that were done to spread radical Islam. That is not something that America had anything to do with.”

On MSNBC’s “Morning Joe”, Sen. Paul asserted GOP hawks “created” ISIS.

“ISIS exists and grew stronger because of the hawks in our party who gave arms indiscriminately,” he said. “They created these people.”

But Santorum, who touted his national security credentials, took issue with Paul’s comment.

ABC News' Tom Thornton contributed to this report.