Final answer:
Trade unions are powerful organizations that protect workers' rights, with a history of gaining legislative protections for collective bargaining and the right to strike, though they have seen some limitations imposed by acts like the Taft-Hartley Act.
Step-by-step explanation:
Trade unions have evolved from being grassroots organizations that fought for better working conditions to becoming powerful entities with significant legal protections. Today, these unions engage in activities such as collective bargaining and striking to improve the wages, benefits, and overall terms of employment for their members. The history of trade unions is marked by legislative milestones, such as the National Labor Relations Act of 1935, that affirmed the rights of workers to organize and form unions. Further protection came from government endorsement during World War II, although subsequent regulations like the Taft-Hartley Act of 1947 introduced limitations.