Last week Bernie Sanders was asked whether he was in favor of “reparations for slavery.” It is worth considering Sanders’s response in full:

No, I don’t think so. First of all, its likelihood of getting through Congress is nil. Second of all, I think it would be very divisive. The real issue is when we look at the poverty rate among the African American community, when we look at the high unemployment rate within the African American community, we have a lot of work to do.

So I think what we should be talking about is making massive investments in rebuilding our cities, in creating millions of decent paying jobs, in making public colleges and universities tuition-free, basically targeting our federal resources to the areas where it is needed the most and where it is needed the most is in impoverished communities, often African American and Latino.

For those of us interested in how the left prioritizes its various radicalisms, Sanders’s answer is illuminating. The spectacle of a socialist candidate opposing reparations as “divisive” (there are few political labels more divisive in the minds of Americans than socialist) is only rivaled by the implausibility of Sanders posing as a pragmatist. Sanders says the chance of getting reparations through Congress is “nil,” a correct observation which could just as well apply to much of the Vermont senator’s own platform. The chances of a President Sanders coaxing a Republican Congress to pass a $1 trillion jobs and infrastructure bill are also nil. Considering Sanders’s proposal for single-payer health care, Paul Krugman asks, “Is there any realistic prospect that a drastic overhaul could be enacted any time soon—say, in the next eight years? No.”

Sanders is a lot of things, many of them good. But he is not the candidate of moderation and unification, so much as the candidate of partisanship and radicalism. There is neither insult nor accolade in this. John Brown was radical and divisive. So was Eric Robert Rudolph. Our current sprawling megapolis of prisons was a bipartisan achievement. Obamacare was not. Sometimes the moral course lies within the politically possible, and sometimes the moral course lies outside of the politically possible. One of the great functions of radical candidates is to war against equivocators and opportunists who conflate these two things. Radicals expand the political imagination and, hopefully, prevent incrementalism from becoming a virtue.

Unfortunately, Sanders’s radicalism has failed in the ancient fight against white supremacy. What he proposes in lieu of reparations—job creation, investment in cities, and free higher education—is well within the Overton window, and his platform on race echoes Democratic orthodoxy. The calls for community policing, body cameras, and a voting-rights bill with pre-clearance restored— all are things that Hillary Clinton agrees with. And those positions with which she might not agree address black people not so much as a class specifically injured by white supremacy, but rather, as a group which magically suffers from disproportionate poverty.

This is the “class first” approach, originating in the myth that racism and socialism are necessarily incompatible. But raising the minimum wage doesn’t really address the fact that black men without criminal records have about the same shot at low-wage work as white men with them; nor can making college free address the wage gap between black and white graduates. Housing discrimination, historical and present, may well be the fulcrum of white supremacy. Affirmative action is one of the most disputed issues of the day. Neither are addressed in the “racial justice” section of Sanders platform.

Sanders’s anti-racist moderation points to a candidate who is not merely against reparations, but one who doesn’t actually understand the argument. To briefly restate it, from 1619 until at least the late 1960s, American institutions, businesses, associations, and governments—federal, state, and local—repeatedly plundered black communities. Their methods included everything from land-theft, to red-lining, to disenfranchisement, to convict-lease labor, to lynching, to enslavement, to the vending of children. So large was this plunder that America, as we know it today, is simply unimaginable without it. Its great universities were founded on it. Its early economy was built by it. Its suburbs were financed by it. Its deadliest war was the result of it.

One can’t evade these facts by changing the subject. Some months ago, black radicals in the Black Lives Matters movement protested Sanders. They were, in the main, jeered by the white left for their efforts. But judged by his platform, Sanders should be directly confronted and asked why his political imagination is so active against plutocracy, but so limited against white supremacy. Jim Crow and its legacy were not merely problems of disproportionate poverty. Why should black voters support a candidate who does not recognize this?

If not even an avowed socialist can be bothered to grapple with reparations, if the question really is that far beyond the pale, if Bernie Sanders truly believes that victims of the Tulsa pogrom deserved nothing, that the victims of contract lending deserve nothing, that the victims of debt peonage deserve nothing, that that political plunder of black communities entitle them to nothing, if this is the candidate of the radical left—then expect white supremacy in America to endure well beyond our lifetimes and lifetimes of our children. Reparations is not one possible tool against white supremacy. It is the indispensable tool against white supremacy. One cannot propose to plunder a people, incur a moral and monetary debt, propose to never pay it back, and then claim to be seriously engaging in the fight against white supremacy.

My hope was to talk to Sanders directly, before writing this article. I reached out repeatedly to his campaign over the past three days. The Sanders campaign did not respond.