grew stronger during the war. The government put pressure on employers to recognize unions to avoid the sort of turbulent struggles over union recognition of the 1930s, while unions were generally able to obtain maintenance of membership clauses, a form of union security, through arbitration and negotiation. Employers gave workers new untaxed benefits (such as vacation time, pensions, and health insurance), which increased real incomes even when wage rates were frozen. The wage differential between higher-skilled and less-skilled workers narrowed, and with the enormous increase in overtime for blue-collar wage workers (at time and a half pay), incomes in working-class households shot up, while the salaried middle class lost ground. The experience of bargaining on a national basis, while restraining local unions from striking, also tended to accelerate the trend toward bureaucracy within the larger CIO unions. Some, such as the Steelworkers, had always been centralized organizations in which authority for major decisions resided at the top. The UAW, by contrast, had always been a more grassroots organization, but it also started to try to rein in its maverick local leadership during these years. The CIO also had to confront deep racial divides in its membership, particularly in the UAW plants in Detroit where white workers sometimes struck to protest the promotion of black workers to production jobs, but also in shipyards in Alabama, mass transit in Philadelphia, and steel plants in Baltimore. The CIO leadership, particularly those in further left unions such as the Packinghouse Workers, the UAW, the NMU, and the Transport Workers, undertook serious efforts to suppress hate strikes, to educate their membership, and to support the Roosevelt Administration's tentative efforts to remedy racial discrimination in war industries through the Fair Employment Practices Commission. Those unions contrasted their relatively bold attack on the problem with the AFL. The CIO unions were progressive in dealing with gender discrimination in the wartime industry, which now employed many more women workers in nontraditional jobs. Unions that had represented large numbers of women workers before the war, such as the UE (electrical workers) and the Food and Tobacco Workers, had fairly good records of fighting discrimination against women. Most union leaders saw women as temporary wartime replacements for the men in the armed forces. The wages of these women needed to be kept high so that the veterans would get high wages. The South in wartime The war marked a time