I mean, they technically have their own independent power grid, so whether they are their own country or a state, Texans freezing to death would be left to fate, anyway...
I wonder how they would manage imports and exports, for two examples. Or the visa system for visiting the US and its territories? Their own WIC and other (currently federal) social service programs, or are they planning to discontinue them in typical forced-birth fashion? I would really like to see them do it and see if they want what they get.
I'm hoping you forgot the /s, but just in case you're not from the US: no, it's built into almost every financial institution's terms and conditions, at least in my experience. I had to get my mother a pre-paid credit card because she would overdraft regularly, and the bank had no solution. The pre-paid just declines payment, like the good old days.