Although Tobin supported the principle of craft unionism, he was tolerant of unions which advocated industrial unionism under certain limitations. In many ways, the Teamsters were already an industrial union, with wide diversity in membership, and Tobin advocated a moderate line toward industrial unionism in part to defend his own union. When the AFL Executive Council proposed in July 1935 suspending the unions which had formed the Committee for Industrial Organization, Tobin argued that the Executive Council lacked the authority to do so. But once the Executive Council's decision was made, Tobin enforced it and ordered Teamster local unions to cut off relations with CIO unions.