Although some historians feel that the Civil War was a result of political blunders and that the issue of slavery did not cause the conflict, this interpretation fails to consider the two main causes of the war itself: the expansion of slavery, and its entrance into the political scene. By considering the personal opinions of people living in both the North and the South at the time of the war, as well as the political decisions made, one can understand the reasons behind the war, and then determine its inevitability.
The revisionists believe that the issue of slavery was not a major cause of the war. Some argue that the war was caused by careless decisions made by politicians, who caused people to react with emotions that were out of proportion with the issues involved. Others feel that the slavery problem could have been solved without war. The problem with these theories is that the revisionists do not recognize slavery as the main difference between North and South. They also fail to realize that it was not simply political blunders that caused the war, but the discussion of slavery publicly among politicians.
In his theory of the war, Michael Holt primarily considers the timing of the conflict. He feels that the breakdown in the two party system created a panic among citizens and that this panic erupted into war. The only problem with this theory is that it is not the citizens of a country who decide whether or not to go to war, it is the politicians. The reason that slavery could exist without war in the United States until 1861 was because up until that time there was always enough land to expand. It was when the amount of land available for expansion became scarce that the North and South began to feel friction as to who would control more states, free or slave. The South wanted more slave states, where the North wanted more free states, to give them more land and power in the Senate. That tension, when publicly addressed, erupted into war. Both the North and the South felt that the other was trying to enslave them. This feeling among both Northerners and Southerners made the expansion issue so powerful because the more land and as a result power the South gained, the more afraid the north became; as a result the more the North felt they must prevent the south from expanding.
Arthur Schlesinger feels that the war was fought over the moral issue of slavery. In his essay, "A Moral Problem," he says, " A society closed in the defense of evil institutions thus creates moral differences far too profound to be solved by compromise. Such a society forces upon everyone, both those living at the time and those writing about it later, the necessity of moral judgment." He goes on to say that because slavery was "a betrayal to the basic values of our Christian and democratic tradition," it had to be challenged, however, He fails to realize that the North did not care about the institution of slavery as long as it stayed in the South. South Carolina seceded, because Abraham Lincoln, a Republican, was voted into office. The Republican party threatened the South's expansionism and therefore Southerners felt that they had no other choice but to secede or, "To abandon the institution of slavery to Black Republicanism, and to trust the union for her safety." The Republican party, however, had no intention of ending slavery in the South or freeing the slaves; they just did not want slavery to expand, "Because the scene of intestine struggle will thus be transferred from the south to the North." He does argue that slavery, for whatever reason was at the heart of the conflict between North and South, and that "The extension of slavery...was an act of aggression"

The United States was divided into three groups by the time the Civil War began: those who believed in the complete abolition of slavery, those who were against the expansion of slavery, and those who were pro slavery. Many historians like to believe that the moral aspect of slavery is what made it an explosive issue. As Schlesinger notes, "It was the moral issue of slavery, that gave the