Very interesting[0]. However, he's not under threat;) so I'm still waiting (and will keep waiting, according to the person I originally asked).
I wonder what the strategy is, given that (in my view) it's unlikely the Supreme Court will agree with the Trump admin. Is it performative or will they use it to pressure legislators, and how do they see a route to winning there?
Still, the Wiki does show that it's certainly arguable, so we'll see.
[0] https://en.wikipedia.org/wiki/United_States_v._Wong_Kim_Ark