Among the many buildings torched this past week, one stands out as an odd target: the AFL-CIO headquarters in Washington, DC. While some have speculated that protesters set the lobby ablaze Sunday night because of the labor federation’s failure to pursue racial justice with sufficient gusto, the more likely explanation is that protesters saw it as just another fancy edifice.

That’s a tragedy. The headquarters of the country’s most important labor federation should be widely viewed as a symbol of racial and economic justice. That the union hall was of no special importance to the people rebelling is an indictment of the AFL-CIO. As the DC area local of the Amalgamated Transit Union (ATU) put it in a press release yesterday, “Why did young black and brown workers, frustrated with constant injustice, not view the AFL-CIO as their natural ally with over a century of experience in the struggle for equality? Why did they not recognize that act as burning their own house?”

Some unions, including the ATU, have given a glimpse of the best of American labor — one at the forefront of fighting all forms of oppression. In Brooklyn, when the police attempted to use a city bus last week to transport arrested protesters, the bus driver stepped off and refused to drive it. His union backed him up. In Minneapolis, after a rank-and-file bus driver declined to transport police, his ATU local issued a statement affirming members’ right to refuse to assist police operations. The national Transport Workers Union (TWU), which represents workers from San Francisco to New York, issued a statement saying their drivers are under no obligation to act as police chauffeurs.

All of these workers and unions took their place in the long history of anti-racist action by organized labor in the United States. While far too many perpetrated or ignored racial injustice, some unions, particularly those connected to the socialist or communist left, threw themselves into struggle in a way that provides a model for today.

In 1946, immediately after World War II, New York unionists mobilized in support of the Ferguson brothers, four black men (three of them veterans) who were reuniting after the war in Freeport, Long Island. After being refused service in a white coffee shop, the men were attacked by a police officer who shot and killed two of them (and who was immediately commended by a judge and a district attorney for doing so). Along with the local NAACP, the Communist Party (CP), and other forces, progressive labor unions played a central role in the movement for justice in Freeport. The TWU, close to the CP at the time, led the way. At one rally, a TWU leader linked the struggle against police brutality to anti-colonialist movements, shouting, “Freeport, my TWU, the struggles in India, they are all the same fight.”

In those same years, New York City’s CP-led Teachers Union (TU) also took on the police. An earlier investigation had revealed that more than four hundred New York City police officers were members of the Christian Front, a fascist organization founded by Father Charles Coughlin. Drawing links between antisemitism and anti-black racism, the largely Jewish TU campaigned for the mayor to fire police officers tied to the organization.

In Los Angeles, the postwar years also saw unions mobilize against police violence. In 1948, an LAPD officer shot and killed seventeen-year-old Augustín Salcido while arresting him for supposedly selling stolen watches. The citywide CIO council, a leader in the fight for justice for Salcido, immediately put out a statement: “Mexican-American members of our union in the thousands can testify to the beatings, intimidations, shake-downs, uncalled for arrests and terrorism carried on by the police in the Mexican-American community in Los Angeles.”

The head of the United Office and Professional Workers of America addressed a letter to the mayor on behalf of his members, demanding prosecution: “If [the police officer] is not brought to account, this latest shooting will be a clear sign of official approval for terror against minority peoples.” When the officer was acquitted, the city CIO led a delegation to meet with the chief of police, insisting that he fire the officer.

More recent examples also show how organized labor can commit itself to the struggle against police violence. In 2014–15, a number of unions signed on to the demands of Black Lives Matter (BLM) activists. National Nurses United linked police violence to racial health disparities. In California, UAW local 2865 urged the AFL-CIO to boot police unions from its ranks. The Communication Workers of America put out a statement in support of BLM (though a hedged one that also revealed the reticence of many union leaders to confront police unions).

The participation of labor unions in anti-racist struggles isn’t just an ethical imperative. It’s crucial to the success of the fight against police violence and racism, for at least two reasons.

First, police unions are a central enemy of the movement on the streets. They fight for the most reactionary legislation, mobilize to defend members guilty of the most heinous crimes, and generally flaunt their disregard for civilian governance. However, in most cities and states, police unions are treated as members in good standing of local labor councils and federations. They often work closely with other municipal unions, from firefighters to teachers, to protect labor rights and municipal budgets. Given their size and power, most other city unions are wary of alienating them.

This is an enormous political problem. If the police are to be defunded and reined in, their unions need to be split off and isolated from the rest of organized labor. If police unions are able to maintain a common front with other city unions, they will almost certainly be able to resist any meaningful efforts to restrain them.

Effecting a split will require action from union members themselves. In public worker unions in particular, members will have to push their organizations to identify publicly with the struggle against police brutality. Unions will have to go beyond mere statements and devote real resources to anti-racist struggle. These kinds of actions would widen the gap between cops and other city workers, rendering police unions politically isolated and more vulnerable to progressive reforms.

Second, it’s still unclear where the power to force police reform will ultimately come from. While the tremendous energy put into restraining the police over the last seventy years has often raised public awareness of racial oppression, it has been much less successful in institutionally disempowering the police. Victories have been won against individual police, but few against the system itself.

Significantly weakening the police will require a tremendous amount of social power — overcoming not just the institutional power of police unions, but the capitalist city planners that support expanded policing. To confront those interests, the movement will need to mobilize far more extensive forces than have yet entered the field. It will need to be able to exert power not merely through necessarily brief acts of disorganized disruption, but through organized, nonviolent coercion against capital and the state.

Building an alliance between labor and anti-racist struggles won’t be simple or easy. Many unions are all too happy to align with police unions, while others will pass resolutions galore without any action to accompany them. But rank-and-file union members can push these institutions forward even when their leaders would rather they remain stationary. As the fires inevitably begin to cool, and the question of where the movement goes next arises, these workers are one group that could provide an answer.