[Non-Sequitur]

The legally, duly constituted governments of several states, elected by the citizens and reflecting the sentiments of the majority of them, voted to remove themselves from a civil compact they had willingly entered several decades before.

Since they lacked the authority to do so then their actions were illegal and constituted a rebellion or a civil war, take you pick.

[ZULU]

No.

There is nothing in the Constitution which states a state cannot seceed. The Union was a voluntary association of states, consequently, it was Lincoln who acted illegally by using force to coherce the seceeding states back into the Union.