Citizenship by birthright isn't an exclusively American thing, 34 nations currently practise it. It's protected by the Fourteenth Amendment, can only be repealed by another one (like the 18th was set aside by the 21st). For an amendment to become law, it has to be ratified either by a two-thirds majority of both Houses (Trump hasn't got the numbers) or by a minimum of 34 state legislatures (he's never has anything approaching that kind of support, either).
Ruling by decree is something dictators do.
Hello M2C
This is why the 13th, 14th and 15th amendments are referred to as the "Reconstruction Amendments"...and NOT the "Sanctuary city" amendments...
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