Fox News/screengrabBill O’Reilly interviews Donald Trump.

Fox News host Bill O’Reilly repeatedly challenged a key portion of Donald Trump’s immigration agenda during a Tuesday night interview.

The real-estate magnate and Republican presidential candidate recently unveiled his multi-part plan to clamp down on illegal immigration. Among other things, Trump called for ending birthright citizenship, or the right of anyone born in the US to American citizenship.

However, as O’Reilly pointed out, the US Constitution’s 14th Amendment enshrines birthright citizenship into US law.

“That’s not going to happen because the 14th Amendment says if you’re born here, you’re an American. And you can’t kick Americans out,” O’Reilly told Trump. “The courts would block you at every turn. You must know all that.”

Trump insisted that the Constitution does not grant citizenship to so-called “anchor babies,” a pejorative term used to describe the children of people who enter the country illegally for the purpose of having a son or daughter who would then be granted US citizenship.

“Bill, I think you’re wrong about the 14th Amendment. And frankly, the whole thing with ‘anchor babies’ and the concept of ‘anchor babies’ — I don’t think you’re right about that,” Trump said. 

O’Reilly was incredulous.

“I can quote it! You want me to quote you the amendment? If you’re born here, you’re an American — period! Period!” O’Reilly exclaimed of the Constitution. 

The Fox host later added: “You are not going to be able to deport people who have American citizenship now. And the federal courts will never allow mass deportations without due process for each and every one. And do you envision federal police kicking in the doors in barrios around the country, dragging families out?”

But Trump, citing unnamed lawyers, held his ground on the citizenship issue. 

“Bill, I don’t think that they have American citizenship. And if you speak to some very, very good lawyers — and I know some would disagree, but many of them agree with me — you’re going to find they do not have American citizenship. We have to start a process where we take back our country. Our country is going to hell,” he said.

For the record, the text of the amendment would seem to favour O’Reilly’s interpretation in the dispute. It states: “All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United State.”

O’Reilly also asked Trump if he would be interested in changing the language of the Constitution to comport with how he sees the citizenship issue.

“It’s a long process and I think it would take too long. I’d much rather find out whether or not ‘anchor babies’ are actually citizens because a lot of people don’t think they are,” the developer responded.

Trump has based much of his presidential campaign on his opposition to illegal immigration. His heated rhetoric on the issue — especially his accusation that the Mexican government is intentionally sending “rapists” into the US — touched off a a national firestorm after he launched his campaign. But the controversy has appeared to only fuel his White House bid. Trump has led in almost every recent poll of the Republican primary. 

Watch Trump’s Fox interview below:

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