Reading through the comments the concept of MAD (mutually assured destruction) was the first thing that come to my mind. Unless Texans undertook the route described in Publius’s post #110 MAD would almost inevitably be the result.
Secession isn’t simply spinning around three times while shouting “I break with thee, I break with thee, I break with thee!” There’s a ton of things that must be negotiated as a necessary part of any organized withdrawal.
Our time would be better spent finding ways to minimizing the power of leftists.
Back to 1861.
Had the South returned their representatives and senators to Congress to negotiate an amicable divorce, there would have been three burning issues.
That last one would have been a critically nasty bone of contention in congressional negotiations. The Southern attitude would have been that slaves are property, property is sacred, and thus runaway property should have no protection simply because it crosses a new international boundary. The North would have accepted none of that. A number of historians have stated that that one point alone would have guaranteed an inevitable armed conflict over secession.
There would be bones of contention today, and federal land and debts owed to the federal entity would be among the largest. Thank God we don't have slavery to fight over.
As Lincoln understood, a constitutional amendment and its attendant debate would provide the proper platform to set the terms of divorce. It would be the one technique to get around the Supreme Court's 1869 decision in Texas v. White, where it stated that the Union was permanent and indivisible.