Sen. John N. Kennedy (R-La.) hit back Thursday at Democrats - and Sen. Bernie Sanders (I-Vt.) - over their opposition to funding President Trump's border wall. 

In a "Special Report" interview, Sanders said border security is "enormously important" but he said the wall project is "costly" and "inefficient" and that experts agree with him. 

Trump said earlier this week he'd be "proud" to trigger a partial government shutdown on Dec. 21 if Congress does not approve $5 billion in funds for the wall. 

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Kennedy said on "America's Newsroom," Sanders and many others on the left do not believe "that illegal immigration is illegal" and won't acknowledge that "walls work" along the southern border and in many other countries, like Israel. 

"Legal immigration is good for our country but illegal immigration is illegal and we should stop it because it undermines legal immigration," he said, emphasizing not all illegal immigrants are "bad people."

He stressed that securing the border is a national security issue, since some people who cross illegally are drug dealers, terrorists or gang members. 

Kennedy said the nation's immigration laws are not broken, they're just not being enforced. He said Democrats should not underestimate Trump's resolve when it comes to the wall and a potential shutdown. 

"If I was playing poker with him, I wouldn't call his bluff on this one,"he said, predicting that Nancy Pelosi will not make a deal with Trump. 

Watch the full interview above and see reaction from former ICE Director Tom Homan below. 

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