No, President Trump can’t end birthright citizenship via Presidential decree. But the Supreme Court could if they got disgustingly creative with the 14th Amendment.
It’s happened before.
The Supremes in the late 19th century bought the original argument by corporate attorneys that the world “person” contained in the 14th Amendment was originally penned as “citizen,” but changed to “person” to cover corporations. The 14th Amendment architects all along had intended to apply the 14th’s Amendment’s due process and equal protection clauses to not only freed slaves but also to business corporations. This was the argument promoted with a straight face by Roscoe Conkling, counsel for a railroad corporation angling to be shielded with the same constitutional rights as human persons to avoid having to pay higher taxes. Conkling, by the way, was the last person (and maybe the only person) to turn down a Supreme Court appointment after he had been nominated and confirmed. The reason was he wanted to make more money as a corporate attorney.
We the People have ever since been on the short end of the slew of corporate constitutional rights that have hijacked our representative democracy with High Court decisions overturning scores of democratically enacted laws and regulations protecting workers, consumers, communities and the environment.
What’s to stop the anti-justice, extreme right-wing majority on the current Supreme Court from coming up with some wild rationale today to give Trump what he wants? Who knows what they could come up. Not to give them any ideas, but corporations chartered abroad are in the eyes of US law deemed “alien” corporations. Maybe the Supremes might say children of “illegal aliens” are in fact “aliens” themselves, which are different enough from “persons” to disqualify them from birthright citizenship.
I’d like to think this is completely far fetched and way beyond the reach of the possible. But we are dealing, after all, with an institution that has time and again over 130 years anointed a bunch of legal documents, which is pretty much what corporations are, as possessing the same Bill of Rights, 14th Amendment and other never-intended inalienable constitutional rights as human beings. Take into account the hostility of the majority on the current High Court to cases addressing any number of human rights, and what may seem far fetched is definitely within the realm of possibility.
Of course, what can stop such consideration cold if such an effort become serious is seriously massive organizing and demonstrations in defense of human rights.
That, too, has happened before and helped to deter the worst inclinations of the Supreme Court to protect and promote property rights over human rights.