They were abandoned. Of course the residents took back land they believed was part of their new Nation.
Sumpter was the most publicized and no president would have tolerated an insurrection threatening the Union.
First of all, it was not an "insurrection." The populations of the states held a vote and through democracy they decided they no longer wished to be governed by Washington DC. As the Declaration said, Governments only rule through the consent of the governed, and these people withdrew their consent.
Secondly, in what manner did an Independent South threaten the Union? (other than diverting trade from New York.)
The idiot Slavers brought on their destruction. It was sheer insanity.
Weren't they slavers when they were part of the Union? Wouldn't slavery have continued if the South had not tried to be independent?
Arsenals were not abandoned.
It was clearly an insurrection. There is no constitutional provision for state conventions to declare an end to the Union. The constitution is the ruling document, not the Declaration. It was settled in 1787 that there was NO conditional ratification and no right to leave without constitutional authority.
There was no threat to any Slaver right except the right to be a slaver. All other claims are just attempts to disguise the real issue.
The Confederacy ATTACKED federal institutions. This ensured a war.
Slavery would have continued for some time but would have been legally removed at some point in keeping with the gradual elimination underway since 1808. This could have taken many forms. It would have cost less to just buy the slaves’ freedom and manumit them.
The North fought to preserve the Union, the South to preserve slavery.