JAMES W. LOEWE
When he referred to "the noose" he was connoting one of the major ways the Southern Segregationists and racists maintained white supremacy and Jim Crowe after the Civil War: Lynching. They terrorized blacks and whites who had different views by kidnapping their victims, torturing them, hanging them, and often mutilating their bodies after the murder. They never were convicted because the Southern law enforcement officers were often part of the lynch mob, the judges were usually themselves racist segregationists, and if jurors voted to convict in the few cases that went to trial, they themselves were risking lynching. From 1882-1968, 4,743 lynchings occurred in the United States. Of these people that were lynched, 3,446 were black.
As just one example of Southern States' reasons, see {583044}. Many of the Northern States had passed laws declaring everyone in the state was free and making it illegal to return or assist in the returning of escaped slaves. The Southerners got the Federal Fugitive Slave Act passed which required all Americans to assist in recapturing escaped slaves. It was the Northern States who claimed states' rights were being trampled. The South was vehemently opposed to States' Rights when it came to allowing individual states to decide who was free and who was not. The Southerners had only one fundamental reason for secession—the maintenance of the Negro slavery system on which much of their economy depended as did their sociology, culture, and way of life.