Final answer:
The Wagner Act of 1935, also known as the National Labor Relations Act, was a pivotal law that gave unions the right to organize and participate in collective bargaining, while creating the NLRB to resolve labor disputes.
Step-by-step explanation:
Unions gain a significant portion of their legal power from the Wagner Act of 1935, which is also known as the National Labor Relations Act. This crucial piece of legislation came about during the Great Depression and played a pivotal role in empowering labor organizations by reaffirming workers' rights to organize and engage in collective bargaining. The Wagner Act notably established rules limiting employer interference in union activities, defined unfair labor practices, and created the National Labor Relations Board (NLRB) to settle disputes between employers and labor unions. Congress augmented labor protections by passing the Fair Labor Standards Act in 1938, which introduced maximum hours and minimum wages. Despite subsequent legislation like the Taft-Hartley Act of 1947, which imposed restrictions on union power, the Wagner Act served as a foundation for labor rights and union growth during the mid-20th century.