We're now entering the sesquicentennial of the Civil War -- 150 years ago.
I was a kid growing up in border states (Kentucky and Missouri) during the Civil War centennial in the 1960s, so some of the arguments about what the war was about are familiar to me from childhood.
First of all, I don't think it's any accident that the Civil Rights Act of 1964 was passed during this centennial period -- or that the passage of that act rent the Democratic party apart much as the election of 1860 did. (The effect on the Republican party was spectacularly different, though.)
Second, the contention that the war was about states rights is exactly right -- but what was the states rights dispute about? It wasn't about academic arguments. It was about the expansion of slavery in the new states being added to the west, and the consequent long-term political fallout that would result from various resolutions of this issue.
Edward Ball has a nice article on this topic in the NYTimes http://www.nytimes.com/2010/12/19/opinion/19Ball.html?nl=todaysheadlines&emc=a212
...the declaration of causes written by South Carolina and four of the 10 states that followed it out of the Union — which, taken together, paint a kind of self-portrait of the Confederacy — reveals a different story. From Georgia to Texas, each state said the reason it was getting out was that the awful Northern states were threatening to do away with slavery.
South Carolina: "The non-slaveholding states ... have denounced as sinful the institution of slavery" and "have encouraged and assisted thousands of our slaves to leave their homes."
Mississippi: "Our position is thoroughly identified with the institution of slavery — the greatest material interest of the world. ... There was no choice left us but submission to the mandates of abolition, or a dissolution of the Union."
Georgia: "A brief history of the rise, progress, and policy of anti-slavery and the political organization into whose hands the administration of the Federal Government has been committed will fully justify the pronounced verdict of the people of Georgia."
Several states single out a special culprit, Abraham Lincoln, "an obscure and illiterate man" whose "opinions and purposes are hostile to slavery." Lincoln's election to the White House meant, for South Carolina, that "the public mind must rest in the belief that slavery is in the course of ultimate extinction."
More from me here about that Mississippi declaration.