> non-citizens don’t have any particular rights beyond the Geneva Convention

That's just untrue.

https://constitution.congress.gov/browse/essay/artI-S8-C18-8...

> Shaughnessy v. United States ex rel. Mezei, 345 U.S. 206, 212 (1953); see also Mathews v. Diaz, 426 U.S. 67, 77 (1976) ("There are literally millions of aliens within the jurisdiction of the United States. The Fifth Amendment, as well as the Fourteenth Amendment, protects every one of these persons from deprivation of life, liberty, or property without due process of law.");