France’s crisis keeps getting more extreme, spilling over the weekend into broader protests that precipitated hundreds of millions of euros in damage and nearly 2,400 arrests. The country’s leaders are rightly focused on curtailing the violence. Yet as they seek ways to placate a frustrated populace, they must be careful not to make a bad fiscal situation worse. It’s hard to overstate how dire France’s finances have become, particularly now that worried investors have pushed its 10-year bond yields to almost 5%. If borrowing costs remain this high, the interest rate the government pays will soon exceed the economy’s nominal growth rate. As a result, just stabilizing sovereign debt — currently about 120% of gross domestic product, among the highest in Europe — could require running a sustained primary budget surplus of as much as 2% of GDP. That’s a feat France hasn’t achieved since the 1970s. The politics of achieving the necessary deficit reduction, estimated to be at least €125 billion by 2032, could hardly be more fraught. Among potential savings and revenue meas