As France wonders if its new prime minister, Sébastien Lecornu, can cobble together a government coalition and squeeze through next year’s budget, debate is raging over soaring economic inequality — and the tax system that’s contributing to it.

Lecornu’s predecessor, François Bayrou, was toppled in September over a series of belt-tightening proposals widely accused of clobbering the middle and working class while giving a free pass to the superrich. Now, with centrist Lecornu in talks with the center-left Parti Socialiste to secure its backing, one of the Left’s flagship proposals — a new wealth tax targeting France’s largest fortunes — has suddenly gained traction.

The Zucman tax — so named after Gabriel Zucman, the left-leaning economist who devised it — is a top-up levy that would ensure that those with assets worth more than €100 million pay at least 2 percent of their wealth in taxes every year.