It would seem to me that Texas immigration law is not only unconstitutional, but fails to meet the requirements of and violates the Treaty of Guadalupe. The definition, status of Mexican nationals in the American southwest on what is now US soil, immigration, and movement of peoples between the US and Mexico, is actually defined in part by treaty law, which actually is above even federal law and becomes the “law of the land” per article 2, section 2.
This simple fact certainly makes it clear why border issues including immigration can only be a matter of federal law rather than state law. In fact, somewhat similarly, the Jay Treaty defines these things for the Canadian-US border. The Jay treaty specifically defines the free movement of indigenous peoples over the Canadian-US border, too. No state in the north can take that right away, and no state in the south can violate the treaty of Guadeloupe either.
Nor can the present supreme court where many justices claim adherence to originalism be institutionally ignorant of the power of treaties and their historic relationship to borders, immigration rights, etc. After all, the Jay treaty itself was negotiated by, and named after John Jay, the “original originalist”, if you will, who also served as the first chief justice of
the US Supreme Court.
This makes the actions of the US supreme court not only a matter of US law, not only a constitutional crises of federal authority vs state law, but also a question of international law, especially with respect to long settled nation-to-nation treaties. Only willful ignorance as a form of deliberate incompetence can account for the Supreme Courts action in regard to Texas immigration law, and this can form a basis for impeaching current justices.