I'm having fun with this...I think if Texas seceded it most likely becomes like Puerto Rico

Ah, but would there be a war this time or would the US govt say good riddance? The need for southern industry (and populace to help in the national defense against foreign enemies) was much greater in 1860 than it is now.

Would like to respond to some of the recent posts, but haven't had the time.  Until then, a few posts I've read suggest that some might not realize that these secession requests have all been for peaceful secession.  

Again, secession is highly unlikely and as far as I'm concerned, this discussion is simply a hypothetical one for the sake of intellectual exercise.   But, presuming that secession is peaceful, I think it could be safely assumed that for that reason, and probably more importantly because of the geographic location of Texas, that the  U.S. would consider Texas an ally and would afford it no less, and likely much more, protection than it gives Mexico and Canada.    Ponder that some and you will have a headstart on what my response  will  be regarding Texas' military requirements and related budgetary matters.