Although most states had not officially seceded, it was almost certain those states were going out of the Union. Forts and armories were taken by those states to prevent them being used against the states in case they did secede and to prevent them from being taken by mobs of Southerners. States have a basic right to protect their state and their people. In some cases receipts were given to the Feds for arms and equipment taken.
Northern actions had already pushed Southerners over the edge. John Brown's raid to incite a slave rebellion had been widely praised by Northerners. Abolitionists burned cities in Texas and fomented slave rebellion in the summer of 1860. Basically, parts of Dallas, Denton, Pilot Point, Belknap, Gainesville, Black-jack Grove, Kaufman, Navarro, Waxahachie, Henderson, Jefferson, Tyler, Georgetown, Bright Star, and Austin either burned or suffered arson attacks that were thwarted. Many of these attacks happened on the same day. A number of the arsonists were caught and confessed.
These actions matched what abolitionist groups had been proposing be done to the South. On December 14, 1859 on the floor of the House, Clement Vallandigham read the contents of an antislavery circular that had been "extensively circulated throughout the northern, western, and southern States of this Union, and which contains the plans of associations to be formed for the purpose of carrying on armed hostilities against a portion of this Confederacy." Among the circular’s contents:
Our plan is –
1. To make war (openly or secretly, as circumstances may dictate,) upon the property of the slaveholders and their abettors – not for its destruction, if that can be easily avoided, but to convert it to the use of the slaves. If it cannot be converted, then we advise its destruction. Teach the slaves to burn their master’s buildings, to kill their cattle and horses, to conceal or destroy farming utensils, to abandon labor in seed-time and harvest, and let crops perish. Make slavery unprofitable in this way if it can be done in no other.
That's exactly what happened in Texas in the summer of 1860.
Obviously, the South WAS in rebellion even before it seceded, and was determined to use military force in situations where the Founding Fathers had spent years in patient negotiations, after the war, to remove British forces from the United States.
The South had spent far more years than that arguing peaceably that the personal liberty laws of many Northern states violated the Constitution with respect to the return of fugitive slaves. Here is what some distinguished Massachusetts lawyers said about their personal liberty laws (From the Philadelphia Public Ledger of December 20, 1860; my bold font below):
THE CITIZENS OF MASSACHUSETTS AND THE PERSONAL LIBERTY BILLS
Chief Justice Shaw, B. R. Curtis, Joel Parker, and other citizens of Massachusetts equally distinguished, have addressed a letter to the people of that State on the Personal Liberty Bills, which they declare to be unconstitutional. They urge strongly the repeal of them and say:
... We would repeal them under our own love of right; under our own sense of sacredness of compacts; ...
... we firmly believe that the men from whom the worst consequences to our country and ourselves are likely to proceed, have no wish that these laws should be repealed, and no disposition to use any threats in reference to them. On the contrary, they desire to have them stand as conspicuous and palpable breaches of the national compact by ourselves ...
Shaw was Chief Justice of the Massachusetts Supreme Court. Curtis was a former Associate Justice of the US Supreme Court who resigned in protest of the Dred Scott decision. Parker was professor of constitutional law at Harvard and former Chief Justice of the New Hampshire Supreme Court.
Here is one example of appeal to the court system against this Northern nullification of the Constitution. From Prigg v. Pennsylvania (SCOTUS, 1842; my bold again):
The clause manifestly contemplates the existence of a positive, unqualified right on the part of the owner of the slave, which no state law or regulation can in any way qualify, regulate, control or restrain. The slave is not to be discharged from service or labor, in consequence of any state law or regulation. Now certainly, without indulging in any nicety of criticism upon words, it may be fairly said, that any state law or state regulation which interrupts, limits, delays, or postpones the right of the owner of the slave to the immediate possession of the slave, and the immediate command of his service and labor, operates, pro tanto, a discharge of the slave therefrom.
Northern States kept flaunting the Constitution. The last fugitive slave returned from Massachusetts was in 1854 and large numbers of them were living openly in some communities in the North. A thousand fugitive slaves living openly in Chicago left for Canada when the Lincoln administration started enforcing the fugitive slave law there in early April 1861.
Once Southern states started seceding, several Northern states amended or repealed their personal liberty laws. But it was too late. The years of nullification of the Constitution by Northern states had tilted the scale toward secession.
And do you claim that "almost certain" makes "rebellion," "insurrection" and "domestic violence" against federal property and people somehow legal? Does "almost certain" turn federal property magically into state property? I don't think so.
"Forts and armories were taken by those states to prevent them being used against the states in case they did secede and to prevent them from being taken by mobs of Southerners.
I've never seen where "mobs of Southerners" were EVER used as the excuse for these seizures -- what is your source?
Your other reason -- "prevent them being used" by the North -- was certainly the reason given, but how is that reason legal? Federal property and people were still federal, and violence against them was still rebellion, insurrection and/or "domestic violence."
"States have a basic right to protect their state and their people. In some cases receipts were given to the Feds for arms and equipment taken."
And those "receipts" were worth what? And states have a basic right to what? To assault and confiscate nearly unmanned FEDERAL forts? Which law says that?
"Northern actions had already pushed Southerners over the edge."
Nonsense. The South was content to work through normal politics under Southern sympathizer President Buchanan. Indeed the real issue in the 1860 election had nothing to do with ABOLISHING slavery -- instead it was Senator Jefferson Davis' resolution of February to defend slavery in the states & territories, and also guarantee returns of fugitive slaves from Northern states. Naturally, Candidate Lincoln opposed Senator Davis' resolution.
"The South had spent far more years than that arguing peaceably that the personal liberty laws of many Northern states violated the Constitution with respect to the return of fugitive slaves."
Your argument that "personal liberty laws" somehow violate the Constitution has to be utterly insane, and I challenge you to seriously defend it, here on FREE REPUBLIC!
"Northern States kept flaunting the Constitution."
And you can cite Constitutional language to prove this claim?