Three words: Richard Milhous Nixon.
In 1970, Nixon created the Environmental Protection Agency–one of the most destructive government agencies there is–by executive order. That same year, he also signed the Clean Air Act of 1970 into law, which “greatly expanded the federal mandate by requiring comprehensive federal and state regulations for both stationary (industrial) pollution sources and mobile sources. Federal enforcement authority was also significantly expanded.”
In the same year, Nixon signed a bill creating the Occupational Safety and Health Administration (OSHA) “to assure safe and healthful working conditions for working men and women by setting and enforcing standards and by providing training, outreach, education and assistance.” While everyone wants a safe work environment, an expensive, overreaching federal agency is not the way to make it happen.
Nixon was a Republican. According to Wikipedia, Nixon favored a “New Federalism,” defined as “the transfer of certain powers from the United States federal government back to the states.” That all sounds great on paper. However, the legacy he left with OSHA and the EPA alone tell a different story.
Bottom line: “Republican” does NOT equal “Conservative.”