Mass industrial unions were created in the USA during the mid-1930s as a result of a series of bitter and extremely violent battles between workers on one side and capitalists and their police. National guards and hired thugs were used and spies employed by detective agencies were sent to infiltrate the labour movement. Labour legislation, most of it during FD Roosevelt’s “New Deal” Federal government encouraged the organising drive of the unions. In 1934 the US adhered to the International Labour Organisation that had been set up under the League of Nations in 1919. The Wagner Act (National Labour Relations Act) protect the right of workers to organise and elect representatives to engage in collective harmony. (Without vigorous working class action the Federal “pro-labour” legislation would have counted for nothing.)
In 1936 the United Rubber Workers organised the first large sit-down strikes. Workers continued to occupy their plants, but did no work, and prevented scabs being put in their jobs (the traditional method of breaking strikes). They won recognition at Goodyear Tyre and Rubber Company. In Flint Michigan, the United Autoworkers occupied the General Motors Plant. In the same year the anti-strike breaking act (Byrnes Act) made it unlawful to transport strike breakers in inter-state or foreign trade.
The 1937 Walsh-Healy Act established a minimum wage, overtime pay and safety standards on all Federal contracts. General Motors recognised the UAW (CIO) agreeing not to victimise trade unionists in future.
Violence did not cease to be a feature of labour-capitalist relations: ten people were killed and 80 wounded in Chicago in the so-called “Memorial Day Massacre” during a strike by steelworkers, when police attacked a crowd of men and women who were backing the workers in their dispute with “Republic Steel”. The strike was broken after five weeks. The US Steel Corporation recognised the steelworkers organising committee and agreed to an 8-hour day and a 40 hour week.
Workers, some of them organised and influenced by Trotskyists organised rudimentary working class self-defence militias.