It was the mistrust of the Government to do its job and to not interfere with the rights of the people as guaranteed by the Constitution. The Constitution is (or was) a prenuptial marriage contract between the Government and the peoples of the various states. Our federal Government is like a man with (for now) 50 wives.
It is now, as it was then, that the Government has violated that trust between the man and his wives by seeming to have a different agenda than what is believed to be in the best interest of all concerned who the marriage contract has been made with. As in the War between the states Political Interest have superceeded the Public Interests.
for example as with the Illegal Immigrants of today, the Slaves of 1860 were not U.S. citizens either. Yet they have the same function of providing "cheap" labor. Do we commit the same mistakes we did in 1865? I hope not, but it is possible because we have forgotten the lessons of trust and mistrust and covered it with a lesson supposed moral rights vs supposed moral wrongs. Citizenship in the United States is a privelege. A privelege is NOT a right.
And what of the Slaves of 1860? Once they had served their political purposes in the 1870's of the flandering Husband (the Government) they were dumped until they once again in the 1960's became politically expediant again. Is that the pattern we wish to repeat? I would hope not.
The only way this country has survived for the 225 plus years is that it has been a country of equal, fair and just laws for its citizens, and that those laws have not been intrusive upon the freedoms of those same citizens as guaranteed under the Bill of Rights. Government is not the master. It is supposed to be the servant. That is what the people faced in 1860 and that is what we are facing today. Is the Government the Servant, or is it we who are the servants of the Government?
That is the question of "States Rights". When the people lose faith in their federal government they have no choice but to turn to their states governments to solve their complaints. And that solution may be a divorce if history was to repeat itself.
On a side note I do not believe that there will be any secessions of States. But, a dissolution of the United States is a possibility and may come with the collapse of the United States Dolllar.