How did the New Deal affect trade unions?
Unions largely benefited from the New Deal, with some exception. As part of the National Recovery Act, every industry was required to adopt a code which specifically provided for the right of workers to organize. Many labor organizers interpreted this provision to mean that President Roosevelt encouraged workers to join labor unions. The Congress of Industrial Organizations (CIO) was organized by John L. Lewis, largely in response to this endorsement. When the Unions which comprised the CIO were at first expelled by the American Federation of Labor (AFL) the two soon competed with each other for memberships, resulting in a large increase in union membership. At one point the United Auto Workers went on strike. President Roosevelt did not approve of the strike, but would not send in troops to break it up. As a result, the auto manufacturers ultimately signed a contract with the UAW.
At one point, President Roosevelt became angry with the CIO for its intransigence in bargaining with Republic Steel Corporation. When Roosevelt criticized both, John L. Lewis retorted:
It ill behooves one who has supped at labor’s table and who has been sheltered in labor’s house to curse with equal fervor and fine impartiality both labor and its adversaries when they become locked in a deadly embrace.
Roosevelt's remarks led Lewis to support the Republican nominee for President in 1940; however labor unions as a whole were and have remained loyal to the Democratic Party, largely as a result of the favors received during the New Deal.