Publicly, government officials have been busy assuring journalists and others that they are not afraid of the strike action, which has come to be called “the Dec. 5 wall.” But the walkout and the underlying social discontent call into question Mr. Macron’s apparent triumph over the Yellow Vest movement, seen up until now as a crucial moment of his reformist presidency. Unions are predicting a huge turnout on Thursday.

Jean Garrigues, a political historian at the University of Orléans, said, “The victory doesn’t seem to have rehabilitated Macron.” This week’s protest is “the reflection of a crisis in French society, one that can explode at any moment,” he added. “There’s real anxiety over the future.”

Mr. Macron’s hasty $19 billion check to bolster purchasing power in the form of tax cuts and income supplements for low earners did help tamp down the Yellow Vest demonstrations.

But some analysts, like the economist Daniel Cohen of the École Normale Supérieure in Paris, have pointed out that the cash did not settle underlying French social dislocation linked to globalization. The senior Élysée official acknowledged that citizens were in effect saying that they had not seen enough improvement to their daily lives.

The strike has been called to protest Mr. Macron’s proposed overhaul of the byzantine French pension system, one of the world’s most complicated and generous, which is currently headed for a deficit of about $19 billion. Some railway workers, for instance, can retire at 52, and average retirement ages are among the lowest in the industrialized world.