The subtle irony of using the Declaration of Independence, a document that declares that all men are created equal, and endowed by their Creator with the inalienable right to liberty, to justify the disbanding of the Union over the supposed right of some human beings to own other human beings, is just too rich for words.
If there was tyranny rampant in the United States prior to the Civil War, it was nowhere more evident than in the antebellum South.
In the years leading up to the Civil War, most (if not all) conflicts were centered around the issue of slavery.
From the debates on the three-fifths clause in 1787, to the compromise of 1850, they all revolved around the South's "peculiar institution." The end result was inevitable.
Many want to retool the issues leading up of the Civil War, and the South's attempt at destroying the Union, to make them seem more patriotic, more noble even, and palatable to today's Americans, but to do that, one must ignore the fact that a moral abomination existed in the same nation that stood on the inalienable rights of man to life, liberty, and the pursuit of happiness.
Requiem æternam dona eis, Domine; In memoria æterna erit justus, ab auditione mala non timebit.
Beauseant!
No, they didn't. The severe crisis of 1833 revolved around the Tariff of Abominations and South Carolina's attempts somehow to repeal it. Slavery wasn't involved.
Brush up sometime. The whole Civil War was about political power, money, and destiny. The Republicans put together a faction capable, through its combinations of interest and propaganda, of dominating the entire country (look up "Gilded Age" sometime), and the South walked.
The Constitution was not, and is not, a suicide pact, as has been said repeatedly.
all men are created equal
This simply means no man is born a king. It's a rejection of feudalism.
inalienable right to liberty
This expands on the previous point by asserting that men have the right to govern themselves, and not a monarch, which is known as political liberty. The European monarchs of the time were quite dismissive of this concept, asserting that the subjects would never succeed in this.
Thus Free Men have a right to form governments among themselves and agree on the course of their actions without the interference of self declared rulers. This would include those who use their position to abuse their powers by going beyond them. This is called usurpation. For that reason, Mr. Lincoln was referred to as a usurper.
The fact that the South excercised rightful powers in pursuit of denying those rights to others not of their political nation doesn't negate the right. It just makes it a less than advisable excercise.
Perhaps you didn't understand the document, since you appear to have a pretense to royalty of your own. In psychology, this is known as delusions of grandeur.