Strikes work.

On Tuesday afternoon, the Chicago Sun-Times reported that the Chicago Teachers Union (CTU) planned to call a strike authorization vote to keep students from returning to schools in the middle of the COVID-19 pandemic. A few hours later, the city government cancelled a plan to bring students back to schools two days a week and announced that fall classes would instead be held entirely remotely.

Mayor Lori Lightfoot, of course, doesn’t credit the potential strike for the abrupt change in city policy, claiming the decision was about science rather than teachers threatening militant workplace action. But she previously supported a plan that claimed it was safe to bring students back to school buildings two days a week.

Given that CTU has repeatedly shown it can pull off popular and successful strikes like the one it carried out last fall, and that Lightfoot was moving full-steam ahead with reopening schools in the fall before the union’s announcement, it’s clear the possibility of yet another teachers strike forced her hand in stopping the reopening. Thank God for that.

Demands for remote learning have grown more intense over the summer, as teachers say that school districts are woefully unprepared to prevent the rapid spread of COVID-19 to students and school staff. On July 28, the School District of Philadelphia announced it would conduct fall classes remotely, after months of worker and parent pressure organized in large part by the Caucus of Working Educators, a rank-and-file caucus of the Philadelphia Federation of Teachers.

And on Monday, teachers across the country rallied to demand safe schools in a coordinated day of action organized by a coalition of teachers unions and joined by the Democratic Socialists of America. Teachers tied the demand for remote learning during the pandemic to demands to better fund schools and to remove police officers from school buildings.

Also on Monday, United Teachers Los Angeles (UTLA) reached a remote teaching deal with the Los Angeles Unified School District (LAUSD). LAUSD had already agreed in principle to keep school buildings closed in mid-July, following union demands. Like CTU, UTLA conducted a massive, successful strike in 2019.

Quite literally, the lives of enormous numbers of children, teachers, school staff, and parents have been saved thanks to teachers threatening to strike.

The wins in Philadelphia and Los Angeles and the dramatic shift in Chicago illustrate an important point: when workers can credibly threaten to shut down their workplaces, they have the power to win big. And they can win not just for themselves, but for everyone.

Thanks to organized teachers, hundreds of thousands of children will no longer face the threat of going to crowded, unsafe schools in the middle of a deadly pandemic. As teachers in other parts of the country turn up the pressure, that number will probably reach into the millions.

Even the executive council of the national American Federation of Teachers — usually quite moderate — announced in advance it would support local teachers unions who struck over schools reopening in unsafe conditions. The support of the national union, combined with the demonstrated fact that worker and community pressure works, also raises questions about those teachers unions that are not pushing for remote-only instruction in the fall.

Unfortunately, some union locals like New York City’s United Federation of Teachers (UFT) have given a muddled and ambiguous response to the situation in New York. The UFT’s rank-and-file caucus, the Movement of Rank-and-File Educators, has taken a leadership role in pushing to keep schools closed until they can safely reopen. But the caucus lacks the immense resources of the union leadership, who have shown little interest in organizing workplace action to keep teachers and students safe.

The stakes couldn’t be higher. New York City has been an epicenter of COVID-19, and the student population is immense. There are roughly 1.1 million New York City public school students, one in every three hundred people in the United States.

Unions like the UFT should take a page from others like the CTU and act to prevent their members and students from walking into a deadly situation in the fall. The best way to do that, as we just learned from Chicago, is through organizing to strike.