The DoI is essentially a moral document, declaring what the people have the right to do. None of the Founders were stupid enough that they weren't fully aware that any group of people could do anything that someone else didn't stop them from doing. They addressed what people had a moral right to do.
So what were the "these ends" they referred to that the destruction of which would morally justify the alteration or abolition of the government?
It's the rights defined as being inalienable: to life, liberty and pursuit of happiness.
Surely no conservative American would defend the Bolshevik Revolution. It was perpetrated by people who were unhappy with their government and wanted to change it. Was this their Right, as defined by the DoI? Nope, because their revolt was not for the purpose of protecting or providing for those Rights that could alone justify such action. Indeed, it was implemented with the specific intention of denying those rights to those who disagreed.
Similarly, for one to appeal to the DoI as justifying secession in 1860, one must demonstrate why and how the Unites States government had become "destructive of these ends," or destructive to the people's Right to Life, Liberty and the Pursuit of Happiness.
Since, unfortunately, secession was undertaken specifically and explicitly for the purpose of continuing to deny those Rights to a very large percentage of those States' population, indeed in the case of at least two states a majority of the People.
Therefore, the secession of 1860 cannot be justified by the principles outlined in the DoI.
Which is not to say that secession for other reasons might not be fully justified by those same principles.
Can we be in clear agreement that the Federal Government, right now, is indeed destructive of these rights: abortion, drug laws (given legitimacy though they be unlawful), the assassination authorization capability of the NDAA, 'regulation' of industry (like incandescent lights), and so forth?
More importantly, the Declaration was an explanation for what was already an established fact.
The American Revolution began 15 months before the DoI was issued. The DoI was a formal, very well reasoned, and unified declaration of the 13 British Colonies as to their causes and moral justifications for Revolution against the Crown. It was so compelling, that a large percentage of the British political class agreed with them!
There were no legalistic dodges or pretensions that British law allowed it. Every man who signed it knew they put their lives on the line by doing so, and willing did so.
To compare the DoI with the watered down complaints the slavers pumped out attempting to justify secession from a nation who had done nothing to them is beyond obscene.
They used the election of Lincoln and sectional differences to do what they had long wanted to do... create a slave empire where they had unlimited power.
Lincoln's election was simply a convenient excuse for what they had been attempting for over 3 decades. They thought Lincoln would be a weak and ineffective President who would not be able to stop them.
They were so arrogant, so full of bravado, so ignorant of what they were unleashing on themselves, and so-so tragically wrong.
“Let me tell you what is coming. After the sacrifice of countless millions of treasure and hundreds of thousands of lives, you may win Southern independence if God be not against you, but I doubt it.
--- Sam Houston, Governor of Texas, April 19, 1861.
I tell you that, while I believe with you in the doctrine of states rights, the North is determined to preserve this Union. They are not a fiery, impulsive people as you are, for they live in colder climates. But when they begin to move in a given direction, they move with the steady momentum and perseverance of a mighty avalanche; and what I fear is, they will overwhelm the South.”
Source: http://declaringamerica.com/houston-address-on-secession-1860/
It really was one of the greatest miscalculations in history. The only greater I can think of was Hitler invading Russia and then Declaring War on the United States within six months of each other.
What the hell could have they been thinking?
The Declaration of Independence was a propaganda document, perhaps one of the most effective such documents ever written.
And that is a good thing.
It is important to note that one of the complaints against George III was that he refused his assent to laws passed by the local governments. Another is that he was inflicting laws passed by England on localities outside their jurisdiction.
The founders certainly recognized that law was needed, while law was restricted in scope and jurisdiction.