Then, as now, they faced owners who “notoriously squeezed the maximum profit at the smallest cost from their lines.” And in the reactionary backlash that followed the end of the First World War — embodied in the Red Scare and Red Summer of 1919 — railroad management “embarked on a campaign to destroy union representation on their roads.” The risk of unemployment, Davis writes, “was exploited as management sought to instill fear in railroad workers” in order to cut wages and change work rules.

In 1920 and 1921, railroad companies slashed jobs, reduced pay and began to outsource work to subcontractors in order to dilute the strength of railroad workers. By the summer of 1922, worker anger with the railroad companies reached a boiling point. On July 1, leaders of the skilled and semiskilled railroad unions announced that more than 400,000 workers had walked off the job.

What followed was months of violence and industrial unrest. Backed by the Railway Labor Board — established in 1920 to arbitrate between employers and workers but effectively a tool of the employers — railroad companies hired strikebreakers to replace skilled and semiskilled laborers as well as private security forces to protect rail lines and repair shops. In multiple cities, armed company guards opened fire on striking workers, killing several and escalating the conflict even more. Governors in several states called out the National Guard to assist strikebreakers, and President Warren G. Harding’s attorney general, Harry M. Daugherty, directed federal agents to assist the railroads.

The strike all but ended in September 1922, after the reactionary Daugherty won a sweeping federal injunction against the striking workers. They had been beaten, but not entirely and not for good. The experience of the 1922 strike would help inspire workers, over the next decade, to build the kind of political power needed to regain lost ground. The successful industrial organizing of the 1930s owes a good deal to this labor rebellion of the 1920s.

Today, even with the surge of union activity in fast food and other service-related industries, private-sector unionization is still at its lowest point since the passage of the National Labor Relations Act of 1935. And yet, as we’ve seen, where unions are strong — or at least, where they have strength — they are still able to challenge the rapacious and exploitative behavior of business owners and employers.

This more recent episode, then, is a potent reminder that the single best thing President Biden and the Democratic Party could do for workers is to give them the tools and support to build power for themselves. Which is to say that while Democrats do not have the votes to overhaul labor law and protect the right to organize in this Congress, if and when they do, they must.