With the outcry over developments in Kansas strong in the North, defenders of slaveryincreasingly committed to a way of life that abolitionists and their sympathizers considered obsolete or immoralarticulated a militant pro-slavery ideology that would lay the groundwork for secession upon the election of a Republican president. Southerners waged a vitriolic response to political change in the North. Slaveholding interests sought to uphold their constitutional rights in the territories and to maintain sufficient political strength to repulse "hostile" and "ruinous" legislation. Behind this shift was the growth of the cotton textile industry in the North and in Europe, which left slavery more important than ever to the Southern economy.