[wastoute]

I read that there was every expectation that States COULD secede from the Union and that, in fact, the Commonwealth of Massachussetts had threatened to secede some dozen times prior to 1861, and no one expected that they would be invaded had they done so. In fact, I heard there was a "Kentucky Resolution" drawn up in Congress decades before the War that essentially stated a State could leave the Union at will. In this light, Ft Sumter was fired on when the "squatters" refused to leave.

[x]

There was some talk of secession in Massachusetts during the Jeffersonian era, especially at the time of the War of 1812, but I don't think it was as common as you say. It never got very far, but if it had, particularly during the War of 1812 the result could possibly have been war. After that war it was Virginia and other Southern states that asserted the permanence of the union.

Wild threats of unilateral secession, in Massachusetts or in South Carolina, don't prove that it was legal or would have been accepted as legal by the rest of the country. It was a way of expressing dissent or making one's voice heard through threats.

The Kentucky Resolution seems to have more to do with nullification than with secession. The problem with such unilateral declarations by states is that they could say whatever they liked and it's hard to know how much validity to give their claims.

Arguably, the country could have survived the secession crisis without war. What happened was that the rebellious state governments bound together to form a government that was intent on power and expansion at the expense of the union. That came to a head at Fort Sumter and sparked the war. Had the standoff continued longer peacefully, it might have been resolved politically.

There is something monstrous about South Carolina's immoderation and ingratitude. They had wanted the fort. Fort Sumter was built to defend them. The Federal Government built the fort, and may have built up the island on which it stood. The fort was no threat to them. Calling them "squatters" and firing on them was an act of great arrogance, irresponsibility and stupidity. If an amicable divorce had been possible before, it wasn't going to happen afterwards.

Had South Carolina worked peacefully, it's less likely that there would have been a war. Had the rebel states not formed their own federation, but waited until disagreements could be resolved politically, it's possible, maybe even probable that there would have been no war. But the existence of a competing national government determined to expand made war inevitable.