For the majority of the nineteenth century, government intervention in business did not represent the interests of American workers. In several high profile labor disputes, including the Railroad Strike of 1877 and the Pullman Strike of 1894, federal troops were sent in to break up strikes that were deemed contrary to the public interest. In dozens of other local strikes, police and state militia were used for the same purpose.
By the turn of the century, however, many Progressives advocated for union recognition, and a turning point of sorts was reached in President Theodore Roosevelt's intervention in the anthracite coal strike of 1902. Roosevelt forced mine owners under threat of government takeover to negotiate with striking workers. Still, it took thirty years for the federal government to clearly mandate recognition for labor unions, as it did with the National Labor Relations Act in 1934.
While the bargaining rights of unions have declined in many sectors since the 1950s, federal government regulation, itself the product to some extent of union lobbying, has mandated safe working conditions, minimum wage, disability pensions, and other protections that improved the lives of workers.