George Washington University law professor Jonathan Turley said Thursday that it is “insane” for the U.S. to continue allowing birthright citizenship.

The Supreme Court heard oral arguments Wednesday regarding President Donald Trump’s executive order that ended birthright citizenship for children born to illegal aliens. Turley said on “Fox & Friends” that the current issues with birthright citizenship pose a major threat to the country.

“The fact that we are one of the few countries that continues to embrace birthright citizenship is perfectly insane, and it is a great danger to this government and to this republic,” Turley said. ” So the question for these justices is not necessarily if they agree with birthright citizenship. I expect the majority does not.”