Lincoln. His commitment to preserving the United States was so strong and so deep that he was willing to do whatever it took to succeed. Would you li… - James M. McPherson

The great crisis facing the country was the rebellion and anybody in the North who wanted to preserve the Union now found the principal enemy to be those Southern slave owners who had broken up the country. The institution which sustained them and the institution they went to war to defend was slavery. And more and more northerners became convinced of that. As a consequence, a lot of them went the whole way over, from being conservative, pro-Southern, pro-slavery Democrats to becoming radical Republicans. Benjamin Butler is a good example, and Edwin M. Stanton is another one.

While one or more of these interpretations remain popular among the Sons of Confederate Veterans and other Southern heritage groups, few professional historians now subscribe to them. Of all these interpretations, the states' rights argument is perhaps the weakest. It fails to ask the question, states' rights for what purpose? States' rights, or sovereignty, was always more a means than an end, an instrument to achieve a certain goal more than a principle.

Southern political leaders were threatening to take their states out of the Union if a Republican president was elected on a platform restricting slavery.