This is a most unfortunate Labor Day for labor. The labor movement has taken it on the chin repeatedly in the last several decades, but President Trump is the most ruthlessly antilabor president since before the Great Depression.

If the labor movement does not fight harder than it has since Mr. Trump regained the presidency, its future will be dire.

Mr. Trump and his administration have unilaterally stripped collective bargaining rights from hundreds of thousands of federal workers. At the Department of Veterans Affairs alone, 400,000 workers, or 2.8 percent of America’s unionized workers, have lost their collective bargaining rights because of an executive order that will eventually affect more than one million federal workers. Mr. Trump ushered in Labor Day weekend on Thursday by continuing his assault of federal unions, adding the Patent Office, NASA and the National Weather Service to his list of targeted agencies.

Despite this assault on their very existence, we have barely heard a peep from unions. Where is organized labor in the public fight to maintain union jobs, stop the stripping of the safety net and lead the fight for democracy? Other than some statements and angry speeches, the movement has been muted.

If the labor movement wants to fight for its survival, it must return to mass mobilization tactics, reminding Americans that their rights come through working together — not through supporting a president who talks about helping American workers while slashing worker safety regulations, supporting tariffs that raise the cost of consumer goods and stripping workers of their legal rights to contracts.

All this is happening at a time when Americans’ approval of unions is the highest it has been since the mid-1960s.