Well philosophically speaking, a state angry/dissatisfied enough with the USA to actually secede isn't interested in following U.S. law at that point. I'm pretty sure a Texas that seceded would form its own government founded closely on the Constitution the Founders intended but might add some additional clauses to make it more difficult for bad actors to misinterpret it. Texas as its own country would likely be a good ally and responsible trading partner for the USA.
But then again, if California seceded, the government they likely would form would be Cube #2. And that is another very long border for us to have to defend from migrant invasions.