Many times, and apparently a lot closer than have you.
Did you somehow fail to catch what it says about serious actions taken "at pleasure"?
It said that:
Prudence, indeed, will dictate that Governments long established should not be changed for light and transient causes; and accordingly all experience hath shewn, that mankind are more disposed to suffer, while evils are sufferable, than to right themselves by abolishing the forms to which they are accustomed. But when a long train of abuses and usurpations, pursuing invariably the same Object evinces a design to reduce them under absolute Despotism, it is their right, it is their duty, to throw off such Government, and to provide new Guards for their future security.
I am confident the Southern states believed their cause of Independence was neither light or transitory. The Northern states had jiggered the laws to take profits away from them, and they wished to live under a government more to their liking, as was their right articulated by the Declaration of Independence.
That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.
But in fact, they had no causes whatever -- none, zero, nada.
It's not that their reasons were "light or transitory" it's that in fact they had no reasons, period.
In fact, in November 1860, when secessionists began to organize for secession, nothing had changed, nothing.
Their Democrats were still in charge of the Presidency, still a significant force in Congress and utterly dominated the Supreme Court.
Nothing actually bad had happened, and yet they began declaring secession, "at pleasure", meaning not approved by Founders Intent.
DiogenesLamp: "The Northern states had jiggered the laws to take profits away from them, and they wished to live under a government more to their liking, as was their right articulated by the Declaration of Independence. "
But Northern states did no such thing, since Southerners ruled in Washington DC and could have "re-jiggered" any laws they seriously disliked.
So the US government in 1860 was far from "destructive" it was entirely friendly and beneficial, because Southerners ruled it.
The only thing which changed then is the entirely constitutional election of the first Republican president, "Ape" Lincoln.
But Lincoln could not possibly be "destructive" in 1860, because he wasn't even in office.
The Deep South declared secession "at pleasure", period.