TLDR: Texas v. White ruled States cannot unilaterally secede except through revolution or through consent of the States, i.e. the Congress says "Ok, bye." The second is not likely to happen. The first, revolution to secede doesn't seem to be supported by the people if you believe polling data.
It may also be hard to break it up unilaterally into 5 states, as originally agreed to, first the law that admitted it in 1845 & before that, Article IV, Section 3 of the United States Constitution.
why would it be difficult to secede?
A lot of discussion here; https://en.wikipedia.org/wiki/Texas_secession_movements
TLDR: Texas v. White ruled States cannot unilaterally secede except through revolution or through consent of the States, i.e. the Congress says "Ok, bye." The second is not likely to happen. The first, revolution to secede doesn't seem to be supported by the people if you believe polling data.
It may also be hard to break it up unilaterally into 5 states, as originally agreed to, first the law that admitted it in 1845 & before that, Article IV, Section 3 of the United States Constitution.