Even though the Supreme Court upheld the NLRA in 1937, it also issued perhaps the most serious blow to American workers, one not well recognized at the time as the key weapon that would slowly undo workers’ ability to fundamentally redistribute power and therefore wealth: the Mackay Radio & Telegraph decision. In Mackay, the same justices who upheld the NLRA ruled that striking workers could be permanently replaced by strikebreakers. Labor scholars have pointed out the uniquely schizophrenic nature of the court’s rulings that year—one decision affirming that workers have the right to strike and can’t be fired for doing so, but on the other hand, another legal decision that gave employers the right to permanently replace them if they did—which had the effect of firing workers for striking.

Mackay wasn’t well understood at the time as a knockout punch to unions. In just a few short years of serious organizing and real gains via strikes, the societal norms constructed under the New Deal had effectively made it culturally unacceptable to replace striking workers. Another forty-four years would pass and two more rounds of the employer offensive would be launched before President Ronald Reagan weaponized the Mackay decision and replaced 100 percent of the nation’s 12,000 highly skilled air traffic control workers during a strike in 1981. The “societal norms” and “culture” that prevented employers from using Mackay were created because of the brilliant strategy of the early years of the CIO, and by the agency of workers fully engaging the entire community in labor fights.

Imagine the frustration of the billionaires. They had legally secured the right to replace strikers via Mackay, but in effect they had their hands tied by smart worker-organizing strategy. [...]