OMG, no, Indivudual States cannot secede.
But, Texas is still known as A Republic.
But theoreticaly, if a State can leave the Union, and is then embargoed, how do they survive?
Well, The Federal Govt of The USA would probably give them $$$$$$ like they do to other Foriegn Countrys, more so than is given to each State!
Interesting question tho!
Ever wonder why there is a North and South Carolina?
Was it because they were the biggest land mass State, and getting to powerful and Big For their Briches!