The Other Problem with Trump’s NFL Comments
Many are concerned with the NFL's policy change that requires its players on the sidelines to stand for the national anthem. I have seen several criticisms that this policy is a violation of the freedom of speech of the players. They may be right, despite the fact that the NFL is a private organization and the 1st Amendment protects people from government restrictions on speech.
However, there is another constitutional issue with Trump’s comment that “…you have to stand proudly for the national anthem. Or you shouldn't be playing, you shouldn't be there. Maybe you shouldn't be in the country”.
This comment further supports the idea that Trump wants to change citizenship rules. Under current laws, it is very difficult to take away someone’s citizenship, except for in extreme cases. This comment may indicate that Trump wants to make it easier to take away American citizenship from people who oppose him.
In 2017, the Trump administration argued in favor of making it easier to revoke the citizenship of naturalized citizens in Maslenjak v. United States. Luckily, even with a more conservative supreme court, this argument was unanimously rejected.
The president also opposes the idea of birthright citizenship. If you were born in the United States, you are a citizen of the United States. That is birthright citizenship. This has been the case since the ratification of the 14th Amendment in 1868. This idea is opposed by some modern conservatives because they believe that it encourages illegal immigration.
Granted, even if Trump intends to make revoking American citizenship simpler, it is unlikely that he could succeed. He can make it more difficult for people to immigrate to the U.S. or get citizenship, but it is unlikely that he could change birthright citizenship or rules on revoking citizenship without a constitutional amendment.
https://abalegalfactcheck.com/articles/RevokingCitizenship.html