As of 2014, Texas’s per capita GDP in current dollars was about US$61,200, which would make it one of the top 10 wealthiest nations on the planet, equal to Australia. Most of this top 10 is made up of very small and geopolitically irrelevant nations (Liechtenstein, Qatar, Luxembourg, Bermuda, Norway, and Switzerland), meaning that it would be Texas and Australia as the two wealthiest among the serious players.
If Texas went this route (and I would encourage them to do so), then either a substantial portion of “fly over” country would join them, and/or they would have a near immediate surge of refugee/immigrants from FUSA at their borders.
The biggest obstacle I can see is that they would have an urgent need to issue their own currency… the USD$ already being in a steep and irrevocable decline towards absolute zero, so I hope the Texans are quietly working on the currency issue… it would raise the value of a move to Texas by about ten fold for conservatives trapped in “now purple” states who refuse to be dyed blue.
Gov. Abbott has put in motion a Texas Fort Knox, repatriating Texas gold.
http://talkingpointsmemo.com/cafe/with-eye-on-fiscal-armageddon-texas-set-to-repatriate-its-gold-to-new-texas-fort-know
If Texas were to actually leave the forced “union” then they would find it necessary to build a northern wall. 😉