In his opening monologue tonight, Sean Hannity gave liberals - and any American who doubts the necessity of President Donald Trump's travel ban - a serious wake-up call.

The 9th U.S. Circuit Court of Appeals on Thursday unanimously upheld a temporary suspension of Trump's executive order restricting travelers from seven Muslim-majority countries.

"It's time to put petty politics aside and start caring about the safety and security of the American people," Hannity said.

He explained that "our guard is down" as people from those seven nations - Iraq, Iran, Syria, Yemen, Somalia, Sudan and Libya - continue to pour into the U.S.

Hannity said the left is in a "pre-911 mentality" and it's extremely dangerous to our national security.

"If we do not take this threat seriously, it is not a matter of if, it is a certainty, it is a matter of when we'll be hit again," Hannity said. "It's going to happen."

"To all of the people conspiring out of political correctness, trying to stop the president's safety measure, I'm warning you: You will be tied to all of this ... If another 9/11-style attack is committed here in the United States, blood will be on your hands."

Watch more above, and let us know what you think in the comments.

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