Prior to the 1948 presidential campaign, Truman won back the support of labor unions by

Truman won back labor-union support by opposing the Taft-Hartley Act, which restricted unions’ activities. His opposition to the law helped him present himself as a defender of organized labor before the 1948 election. The National Security Act and civil-rights efforts were important parts of his presidency, but they were not the specific way he regained union support.

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