Former U.S. attorney Andy McCarthy said Tuesday that President Trump is "right on the substance" when it comes to the 14th Amendment and potentially curbing birthright citizenship. 

In an interview with Axios, Trump said he intends to restrict birthright citizenship despite those who argue the 14th Amendment guarantees citizenship to all babies born in the United States.

"It was always told to me that you needed a constitutional amendment. Guess what? You don’t," he said.

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"We’re the only country in the world where a person comes in and has a baby, and the baby is essentially a citizen of the United States ... with all of those benefits. It’s ridiculous. And it has to end."

Birthright citizenship has been repealed in a handful of other countries, including Australia, Ireland, France and India. The president argues "birthright citizenship" should not apply to babies of parents in the United States illegally. 

McCarthy said he does not believe that Trump would be able to use an executive order on this critical issue, explaining that Congress would have to act.

"If he signs an executive order, before the ink is dry, there will be an injunction," he said, giving it "less than a 50-50 chance" of holding up in the Supreme Court even if Congress passes a new law. 

Watch the discussion above and read McCarthy's column on the subject. 

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