But birthright citizenship is guaranteed by the 14th amendment to the Constitution, which says "All persons born or naturalized in the United States are citizens of the United States."
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So can the president change that on his own just by executive order? Most constitutional scholars say no because there are only four ways to amend the Constitution and an executive order isn't one of them.
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Here is how the Constitution can be amended:
The first way is houses of Congress propose an amendment with a two-thirds vote, and three-fourths of the state legislatures have to approve it. Twenty-six of the 27 constitutional amendments were approved in this manner.
RELATED: Trump claims he can end birthright citizenship for children of noncitizens
Or houses propose an amendment with a two-thirds vote, and three-fourths of the states approve the amendment by holding conventions. Only the 21st Amendment, which repealed Prohibition, was passed in this manner.
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Another way would be if two-thirds of the state legislatures call on Congress to hold a constitutional convention, and then three-fourths of the state legislatures approve the amendment.
Or finally, two-thirds of the state legislatures call on Congress to hold a constitutional convention, and then three-fourths of the states approve the amendment by holding their own ratifying conventions.
The president says his lawyers have told him he can change it simply by executive order but that will face huge legal challenges.
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