Attacks on the American labor movement have often been swift, dramatic, even violent. The 1947 Taft-Hartley Act was such a widespread attack on labor rights that unionists called it the “slave labor bill.” Reagan’s firing of more than eleven thousand striking air traffic controllers shocked and undermined the entire labor movement. Striking workers were repeatedly killed by federal troops, state militias, local law enforcement, and private guards from the late nineteenth century through the 1930s.

Other attacks on labor have been more nuanced and subtle, but not necessarily less destructive. Labor’s power to effectively strike was eviscerated piece-by-piece by federal court decisions and decisions of the National Labor Relations Board (NLRB) that gradually banned or removed legal protections for various kinds of strikes.

Union busters have chosen this approach to target “salting,” and these attacks may resume under President Trump.