Historians today generally agree that economic conflicts were not a major cause of the war. Though an economic basis to the sectional crisis was popular among the "Progressive school" of historians from the 1910s to the 1940s, few professional historians now subscribe to this explanation. According to economic historian Lee A. Craig, "In fact, numerous studies by economic historians over the past several decades reveal that economic conflict was not an inherent condition of North-South relations during the antebellum era and did not cause the Civil War."