Former President Donald Trump vowed Tuesday to sign an executive order ending birthright citizenship if he makes it back to the White House.

Mr. Trump made the announcement on his social media platform, Truth Social, saying it was time to stop “a reward for breaking the laws of the United States.”

“The United States is among the only countries in the world that says that even if neither parent is a citizen nor even lawfully in the country, their future children are automatic citizens the moment the parents trespass onto our soil,” the former president said.

Birthright citizenship is among the thorniest of legal issues, with most scholars saying the 14th Amendment likely guarantees citizenship to those born here.

But there are dissenting voices, and Mr. Trump called the legal arguments for birthright citizenship “a myth and a willful misinterpretation of the law by open borders advocates.”

During his term in office, Mr. Trump repeatedly said he was preparing to issue an executive order on the matter. But he never followed through on the idea.

it’s not clear what hurdles existed or how they have been overcome.

On Tuesday, Mr. Trump said his promised executive order would instruct federal officers not to recognize the citizenship of someone who is born to illegal immigrant parents.

He said U.S.-born children of illegal immigrants end up claiming social welfare benefits such as health care, some of which benefit the parents that brought them here in the first place.

The 14th Amendment says that all “persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and the State wherein they reside.”

The argument is over that clause about “subject to the jurisdiction.” It has generally been taken to mean automatic citizenship does not accrue to children of ambassadors, who are acting as foreign agents here in the U.S. and as a general matter of policy are immune from prosecution.

But those who challenge birthright citizenship say illegal immigrants aren’t technically under the jurisdiction of the U.S., so they should not be allowed to claim that benefit.

• Stephen Dinan can be reached at sdinan@washingtontimes.com.