Since last year’s election campaign, Macron has sought to shift the balance of power in France, or at least the perception of that balance. He has cast himself as the revolutionary, and organized labor as the revanchists holding on to a vision of the past that he argues is holding the country back. But the unions, and the leftist intellectuals of France who find Macron market-driven, cold, and imperious, are vocal in their critique. It’s an ideological struggle as much as a practical one, and it reveals competing visions of France and its economy. It’s also a fight between labor models of the past and the future, and Macron is the referee.

On national television on May Day morning, Philippe Martinez, the old-school-mustache-wearing leader of the CGT union, decried Macron’s “arrogance” in his treatment of France’s workers. Macron flies around the world, he goes to the United States and Australia, but the president needs “to get a grip on the reality” of French citizens, Martinez said. It’s that “divide” that’s worrisome, he added.

Martinez is a former Renault worker who has led the CGT, a union with historic ties to France’s Communist Party, since 2015. When I met with him in January, along with other journalists in the Anglo-American Press Association of Paris, he conceded a lot of points to Macron. He said he didn’t agree with the president on many things, but respected him as a man of his word who said he’d make certain changes and did, even if Martinez himself wasn’t so keen on those changes. “Macron campaigned on revamping the French economy,” he said then.

So why the strikes? Martinez was asked on television on Tuesday. To protest the Macron government’s social politics, including what he called “social dumping,” or companies’ hiring low-wage workers, Martinez said. There may be other factors. Martinez is fighting for reelection inside the union. The CGT has been losing members. Only about 11 percent of French workers are in unions, although anyone employed in France, unionized or not, has worker protections that go far beyond the at-will-employment model of the United States—as well as functional, if strained, national health care, and universal public education from pre-K to Ph.D.

The unions and other critics of Macron fear that those pillars of the French social-welfare model are at risk. Macron’s supporters see Macron’s job as transforming the economy to create enough jobs so that the tax base can support the social-welfare model. It’s not just a battle between left and right, it’s about competing visions of how to contend with globalization. In recent decades, some former communist workers have begun supporting the hard-right National Front. Martinez on Tuesday said the CGT had blocked that party from participating in its demonstration. “The National Front goes against our values,” he said. (Marine Le Pen, that party’s leader, met Tuesday in Nice with the leaders of other far-right parties from across Europe, pausing to place flowers beneath a statue of Joan of Arc, who looms large in their iconography as a defender of France.)