Actually, union membership did decline significantly during the first few years of the Great Depression, a natural result of declining employment and a general lack of protections for union membership. However, union numbers began to rise again after 1933, with the inauguration of President Franklin Roosevelt. Roosevelt's New Deal pointedly protected the right (and it was asserted as a fundamental right) of workers to organize. This took the form of laws associated with the National Industrial Recovery Act, passed in the first Hundred Days, and especially the Wagner Act, the so-called "Magna Carta of Labor." Both specifically protected the right of workers to collectively bargain. This empowered labor leaders to enlist many more workers, and to fight more effectively for concessions from businesses. John L. Lewis, the head of the United Mine Workers, organized industrial unions into the Congress of Industrial Organizations (CIO) in order to increase the power of these unions. Both the CIO and the American Federation of Labor (AFL) organized workers outside of the crafts which had traditionally been the foundation of the labor movement. While the New Deal provided crucial protections—due in no small part to the actions of labor leaders—union membership also swelled because workers, amid the Great Depression, saw benefits in union membership. In the midst of the widespread hardship of the Depression, Communist activists made significant inroads in the labor movement, in southern mill towns and elsewhere. This gave urgency to Lewis's push for labor activism. Lewis was no communist, and he argued that widespread union membership was an essential bulwark against radicalism.