We've grown accustomed to describing the anti-establishment forces destabilizing politics throughout the West as "populism." Even if it makes sense to use the term for the purposes of description, it shouldn't relieve us of the burden of answering the singularly important question of why the populist style of politics is having an impact at the present moment in so many places.

The answer is injustice.

It might sound obvious, but it's surprising how infrequently the trend gets described this way. For members of a centrist establishment under siege, it's far more comforting to dismiss as illegitimate the motives of those who support Donald Trump's presidency, who voted for Brexit, who travel from the French provinces to don yellow vests on the streets of Paris, and who have empowered populist parties in Poland, Italy, Hungary, Austria, and the Czech Republic. They're racists, xenophobes, rubes, bigots, and entitled whiners who are stomping their feet like spoiled, resentful children, empowering fascists rather than deferring to the experts who actually know how the world works and how to govern the liberal international order.

But of course things look quite different on the other side of the dispute. Until we begin to put ourselves in the populists' shoes and view justice as they do, we will fail to grasp the nature of their upsurge and fall short in our response.

All the way back to Aristotle, political philosophers have recognized that justice is the motor that drives politics. Each class or faction of society has a somewhat different understanding of what justice entails and requires. When members of a class or faction become convinced it has been violated, the normal functioning of political life can become destabilized; when the violation is widely judged to have been great, and the path to redressing the grievance blocked within the current political arrangement, the perceived injustice can even precipitate a revolution — which, for Aristotle, simply meant a change in the prevailing understanding of justice within a given regime.

This is one way to understand the effect of the civil rights movement of the late 1950s and 1960s. The 10 percent of the U.S. population that was African American suffered brutal, systematic racism and discrimination that it understandably considered unjust. Through protests, blacks taught significant numbers of whites to become attuned to this injustice and persuaded them that it needed to be alleviated. The result was a revolution in Aristotle's sense of the term, with the legal apartheid of Jim Crow dismantled in the South and the overt racism of individuals slowly (if imperfectly) worn away by education and moral suasion.

What we have been living through over the past few years is something similar, though the number of the aggrieved is greater as a proportion of the population. With the help of the Electoral College, Trump won the presidency with 46 percent of the vote. Brexit passed with 52 percent. The margins of victory for other populist movements has usually fallen within that range, with roughly half of voters favoring anti-establishment politicians and parties.

These voters tend to come from the countryside, far from the bustling, wealthy, cosmopolitan cities where those with the best educations flock to find well-remunerated work in the globalized ruling class. The tacit deal behind this sociological arrangement was that the members of this ruling class would foster economic growth from which everyone would benefit. The reality, especially since the economic crisis of 2008, has been that those at the center have gotten ever richer while those on the periphery have endured socioeconomic stagnation or worse.

Growing numbers of people feel frozen out of power, their quality of life decaying over time — while the ideology of meritocracy that prevails in the flourishing ruling class drives home the message that their failures are no one's fault but their own. They must deserve their sorry fate. That's a message that in many cases will stifle dissent — at least until it becomes a provocation for anger and resistance in the name of justice.

Every country facing a populist rebellion has its own variation on this story. Tucker Carlson's Fox News rant from a couple of weeks ago has gotten enormous amounts of attention because it distills the American version of the story so well — the one dominated by the rise of finance capitalism that creates a class of super-wealthy overlords who run the country and much of the world for their own benefit while shredding communities and families across the American heartland. Carlson normally has plenty of harsh words for social liberalism on his show, but this time he turned his harshest rhetoric against the conservative movement, for continually siding with the rich without regard for the often pernicious social and cultural consequences of continually empowering capitalism.

Carlson's diatribe was a cry of injustice against the order of things that has prevailed in the U.S. since the election of Ronald Reagan. No wonder that the strongest pushback has come from Reagan-worshipping conservative intellectuals like David French and Ben Shapiro, who doubled down on the center-right variant of the meritocratic ideals affirmed by most of the ruling class: Stop whining. Take responsibility for yourself. If you have talent and a good work ethic, you will succeed. If you fail, that's no one's fault but your own. It's certainly not the fault of bankers, hedge-fund managers, and CEOs, whose wealth is the fruit of their own hard work and which benefits everyone as it trickles down through the economy. Encouraging those who are struggling to blame others for their failures risks building support for big government, which will only strangle the economy, leaving everyone worse off.

Note that this response is silent about injustice — the injustice of shattered lives, families, and communities, but also the injustice of trillion-dollar bank bailouts during the financial crisis while millions of ordinary Americans lost their homes and savings. If anything, it conveys the message that Americans should cease caring about justice, keep their mouths shut, and just continue toiling away, trying to better their lives and their communities. If they live in places without jobs, if their neighbors are dying from addiction to painkillers, they should get the hell out and save themselves. Winners make their own luck. It's the losers and slackers who bellyache about the unfairness of life and look for someone or something to solve their problems for them.

Donald Trump may be a lying, corrupt ignoramus, but he has a better intuitive grasp of the psychology of grievance than his establishment critics do. The politics of injustice demands redress. Populists understand this but too often prefer to direct popular ire toward scapegoats than to lead efforts at real reform. (That's because they often benefit from the very system they denounce for political gain.)

We are awash in a politics of anger. Those politicians who can channel this anger and direct it toward responsible proposals for reform, whether or not they involve the kind of revolution that Aristotle described, will be populists worthy of support.

What won't work is a politics of bland, uplifting happy talk. People are pissed. They want to vote for someone who will take a stand against the entrenched injustices of the present and work to make the country a better place to live and work and raise a family — even if that means breaking more radically from the status quo than any party or politician in a generation or more.

The politics of injustice will be satisfied with nothing less.