Sen. Rand Paul (R-KY) fired back on "Hannity" after Sen. John McCain (R-AZ) blasted the presidential candidate's opposition to the NSA surveillance program.

McCain said on "Fox and Friends" today that he thinks Paul is "divorced from the reality of the nature and the magnitude of the adversary that we face."

McCain added that anyone who thinks that radical Islamic terrorists don't want to kill Americans is "terribly naive."

Paul told Eric Bolling that he doesn't think "we [should] allow fear to let us forget how important the Bill of Rights are."

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"We've had this debate not only about NSA spying, but about indefinitely detaining American citizens," he stated. 

Paul shared that he asked McCain if he would send an American citizen to Guantanamo Bay without a trial and McCain replied "yeah, if they're dangerous."

"I think that shows a fundamental misunderstanding of our Constitution," Paul stated. "Because John McCain doesn’t get to decide if you're dangerous before you’re sent  to Guantanamo Bay, the American court system should. You should get a lawyer. You should get your day in court."

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Paul added that "it begs the question, are we going to let Senator McCain decide who’s dangerous and he just ships them off for life, or are we going to go to a system, which is the Bill of Rights, where everyone gets their day in court?

Watch the video above.