The conference room of the Los Angeles County Federation of Labor was bustling with activity in mid-April. Union organizers distributed flyers in Spanish and English urging, “No Work, No School, and No Shopping on May 1st” and wrangled over the logistics of putting together a march through downtown that they hoped would attract thousands of participants.

Cliff Smith, business manager of Roofers Union Local 36 in Los Angeles, did not mince words when describing the target of the protest: President Donald Trump—the “fascist in the White House”—and the threat facing the country as the midterms approach.

​“It’s important to show business leaders if they back an attempt by Trump to steal the elections that we will shut things down in this country,” said Smith. “May Day will show them that we are serious in our threats.”

The nationwide action, which some organizers are calling a “shutdown” or a “general strike,” is expected to take place with unions sponsoring events in scores of cities across the country. And its aim is to demonstrate the power of workers—and their opposition to the Trump administration’s policies and actions—by withholding their labor.

In Los Angeles, the May Day action has a special significance. It was the site of a massive “Day Without an Immigrant” march in 2006, which drew hundreds of thousands of people to the streets and helped defeat a punitive, anti-immigrant bill in the U.S. Senate. It is also home to a powerful labor federation that represents more than 800,000 workers across the county, many of whom are immigrants.

A theme of this year’s action is “Workers Over Billionaires,” and the Los Angeles march will begin in MacArthur Park, the site of a July raid that involved dozens of federal troops in tactical gear descending on a heavily immigrant community.