Tomorrow, the Wisconsin primaries will determine Donald Trump’s resiliency, which has been hurt by new slip-ups over the past few days. It’s a test for the Republican establishment and anti-Trump voters, who see this electoral landscape as an important opportunity to block the path for the billionaire outsider in the race to the presidential candidacy.

If socio-economic inequality is indeed “the defining challenge of our time,” as Barack Obama, like many others, has maintained, why then has it not resulted in more social tensions, or more people taking up arms? Why, with the damage inflicted by the Great Recession, haven’t the lowly workers and underprivileged middle class revolted yet? In fact, this enigma, which has been a recurring theme among journalists and American political commentators, happens to be illuminated by the rise in power of Donald Trump on the right and Bernie Sanders on the left.

And so, except for the collective movement that was Occupy Wall Street, which was quickly stifled, the people have for the most part kept their anger to themselves, all while losing their jobs and their houses, and watching their purchasing power break down. Part of the explanation stems from the universally verifiable fact that, regardless of a country’s wealth, instability both paralyzes and silences.

To the advantage of the American primaries, this electorally focused collective discontent has suddenly appeared. This is extraordinary, but not without paradox. First, it is rather illogical that Mr. Trump’s supporters, many of whom are at the bottom of the ladder, expect their billionaire savior to bring an end to this systematic injustice. Next is another paradox, in that the effervescence surrounding the candidacies of Mr. Trump and Mr. Sanders shows how in the end, in spite of how poorly they think of politicians, Americans think that the political system can be reformed and be useful to them. That is to say, they have the feeling — or rather they cling to the idea — that exercising the right to vote, despite all its flaws and all the abuses of our democracies, still has the potential to change something.

The United States is far removed from the time of the great collective mobilizations of the 1930s and 1960s. Our behaviors have become categorically individualistic, obliterated by information technology. For a long time, solidarity surrounding specific issues has gone after “class warfare,” even though the argument might be defended that, in their diametrically opposed styles, Mr. Trump and Mr. Sanders revive this very fight. In the labor market’s organization, which is effectively no longer a market, globalization and de-industrialization have furthermore eaten away at the influence of trade unions and, thus, their power to represent their employees’ collective interests. Forty years ago in the United States, more than a third of private sector workers belonged to a union. Today that number is less than 7 percent.

Wisconsin, the location of Tuesday’s Democratic and Republican primaries as well as the cradle of American trade unions, in this regard is quite typical. Its governor, Scott Walker, briefly ran for the Republican presidential nomination and is a staunch anti-unionist who, since coming into office in 2010, has worked to strip worker’s union rights in the name of the sacrosanct individual freedom of choice.

This makes Wisconsin the land of an exceptionally wide divide. On the Democratic side, polls give the “socialist” Bernie Sanders a win tomorrow, by variable margins, against the leader Hillary Clinton. The Republican side shows, even more variably, that Evangelical ultraconservative Ted Cruz, who Mr. Scott supported, would win over Mr. Trump, the Republican iconoclast who confusedly defends both anti-free-trade and anti-union positions. It cannot be stressed enough how desperate the Republican Party must be to consider Mr. Cruz as an alternative solution to Mr. Trump.

The party’s establishment hopes to trip up the real estate billionaire in Wisconsin enough to damage his chances of continuing his rise in the northeastern states, among them New York, where the next primaries will take place in two weeks.

Hence the dystopian question: Will the Republicans end up winning the next presidency, and what would be the aftermath resulting from the sweeping wrath of the working class?