Kentucky voters who supported Republican Matt Bevin in his race for Governor began to recognize a sickening reality in the weeks after the election. Many of them had effectively voted away their access to health care.

Stories about these voters took on a consistently hostile tone, criticizing their foolish vulnerability to racist appeals. That reaction is not only unfair, but deeply counter-productive. White Americans, especially those dependent on disappearing blue-collar jobs for their livelihood are not voting against their interests when they respond to racially-tinged populist appeals. Until we understand the concrete, structural significance of white supremacy to our economy and our political order we will continue to be baffled by the behavior of millions of influential white voters.

Late in his life, Dr. Martin Luther King began to shift the focus of his work beyond race toward poverty. King held out the charitable belief that elevating the awareness of lower income whites to their condition might offer a pathway to a post-racial coalition among America’s lower-earners. He described his insights in a 1968 sermon, centered on his conversations with police while he was jailed in Birmingham. Here’s a digest of his comments on that interaction:

“And when those brothers told me what they were earning, I said, “Now, you know what? You ought to be marching with us. You’re just as poor as Negroes.” And I said, “You are put in the position of supporting your oppressor, because through prejudice and blindness, you fail to see that the same forces that oppress Negroes in American society oppress poor white people. And all you are living on is the satisfaction of your skin being white, and the drum major instinct of thinking that you are somebody big because you are white.”

As he was wont to do, King spread a Hallmark-card sheen on that interaction, but his jailers did not set him free. They did not join hands with him. They did not march by his side then or at any time after.

For all his many insights, King seems to have failed to perceive what professor Derrick Bell would describe thirty years later. In the strictest sense, blue collar white workers were not voting against their interest by supporting racist politicians. They were rallying around their last tie to a form of racial solidarity that for centuries had delivered meaningful, material rewards. Voters in the Kentucky counties most desperately dependent on the welfare state voted overwhelmingly for Romney in 2012 and elected a Tea Party extremist Governor in 2015. By the same logic, that cohort of voters is flocking to Donald Trump and ignoring Bernie Sanders.

The material rewards of racism are as real as the bars that separated King from his jailers. On one side were men who held secure government jobs for life. Though their incomes were modest, they enjoyed guaranteed health care and a pension. The machinery of a deeply oppressive system was calibrated to spare them from its most violent tendencies. Those men saw (and sometimes meted out) the worst abuses that system could deliver. By virtue of the racial heritage they shared with wealthier whites, they enjoyed a thin, but vital degree of protection. Those jailers held down government jobs with pensions for one reason and one reason only – their skin color. And they knew it.

On the other side of the bars were men with few economic prospects, despised, and subjected to relentless oppression, humiliation and violence. The only crime those prisoners had committed was their defiance of white supremacy. King’s jailers recognized that race was the only force keeping them outside that cage. They feared what would happen to them if black citizens were given equal treatment. Many white voters continue to see that same potential in the growth of a post-racial America, their last tie to their modest collection of privileges cut, the last advantages and protections of their race terminated. White support for the likes of Donald Trump or Ted Cruz emerges from a terrible logic that we ignore at our peril.

In King’s lifetime we were already experiencing the dawn of a new global capitalist order, bringing with it innovation, prosperity and disruption on an unprecedented scale. For all our present angst about income inequality, the trend toward extreme outcomes we see today was already in motion by the late 50’s. An economy built more on talent than on muscle respects only one color – green. Racial preferences were standing in the way of a new world of profit. King had a potent ally he never recognized.

As the knowledge economy shifts into second gear it is fueling greater and greater variation in incomes. Those with the education, positioning and drive to get in the game have a chance to reap inordinately large payoffs. Those who do not compete successfully get less than in the past. It is an economy of extremes. That thick layer of predictable, middle income jobs is thinning steadily.

An obvious solution might be to deliver a basic level of income and lifestyle for everyone, without regard for old concerns about “need.” Pay for it with taxes on the higher earners who made it into the express lanes of the knowledge economy. Those who want to reap the rewards of the knowledge economy will be free to do so. Those who either don’t want that high-pressure, high-speed lifestyle, or for some reason cannot perform there, will be prevented from falling into penury.

One glaring political problem blocks this move. A large minority of US voters who might seem like the prime beneficiaries of this reform are determined not to go there. Lower income whites, especially in the South, are not interested in a new deal. They want to restore the old one.

Under the old deal, white men got preferential access to all of the best jobs available. Generations of white families earned their living in the fire or police departments, or worked in road construction, sanitation, or public works. Sons worked alongside fathers in union jobs at a local factory. They had every reason to expect that their children would have a chance to follow in the family tradition.

Global capitalism and the rise of the knowledge economy destroyed that simple, yet dignified way of life. As the demands of competition intensified, political will behind generations of racial preferences broke down. Race and gender-based protections for whites weakened or melted away.

Economic outcomes for those who earned an education, moved to big cities, and poured themselves into an exciting and demanding competition bloomed. Capitalism drove down the price of practically everything except for the labor of a smart, talented, educated human being. Salaries for educated professionals exceed anything broadly available just a generation ago while the range of products and services available for that money has exploded. For many, this is a bright new age of wonder, defined by affluence, freedom and seemingly endless potential.

Those who had hoped to join their uncles at the assembly line, in local government or public service jobs found fewer options available. Most importantly, in political terms they faced fresh competition from those who had been locked out of those roles in the past. People who, from their perspective, were the most American Americans, found their relative lifestyles dented, unable to achieve the economic security a previous generation of blue collar whites took for granted. Meanwhile, for all their continuing struggles, minority families have seen their relative incomes and well-being improve.

Whites with a college education and a chance to earn a living in a professional or technical field seldom have more than a distant attachment to racism, varying by how much they’ve learned or how much exposure they’ve had to a wider world. For those who come from a blue-collar tradition, especially manufacturing, mining or public service families, this new world is a rapidly unfolding catastrophe. They aren’t just falling behind, they are dying off.

Expanded access to Medicaid isn’t merely a poor compensation for what they’ve lost, it’s a stinging insult. White racial solidarity across income levels cannot be dismissed as a sentimental attachment, an opiate for the white masses. It has always been a cornerstone of their well-being. From the perspective of blue collar workers, affluent whites pushing “political correctness” or “diversity” are traitors. Having climbed the ladder they are sawing off the bottom rungs.

What the Trumps and Cruz’s of the world offer these voters is a chance to put the genie back in the bottle. They want to restore an America that reserves its bounty for “good, hard-working” white people, where women know their place and behave as humble, modest women should. Where a white man doesn’t need to slog through years of “socialist indoctrination” at some godless university to earn a chance at honest work. They offer a government that will ‘take my country back’ blocking a mythical wave of greedy newcomers who haven’t earned their place from stealing what little is left over after the wealthy take their share. They promise to put “uppity” minorities in their place, suppressing the supposed wave of crime and general thievery perpetrated by lesser races who would steal from the more deserving.

Want to convince lower income white Americans that they are voting against their interests? Explain how you can offer them something better than white supremacy. When we understand what white supremacy actually delivered for these folks, the scale of our challenge in building a just post-racial society becomes evident.

Perhaps King failed to recognize the depth of the challenge he faced in trying to forge an alliance with lower income whites. That said King didn’t become an American secular saint by setting modest goals. No one who is serious about challenging racism in America should ignore the structural, functional importance of bigotry.

With that obstacle squarely in sight the power of our Goliath becomes clear. So does his weakness. King always insisted that peace was inseparable from justice. Once we recognize that racism in America is more than just a moral compromise or a product of ignorance, we start to see the flaw in our efforts to date. Our approach to racism over the past forty years has placed the bill for white supremacy at the feet of the white families who benefited least. Affluent whites have walked away and retained their accumulated rewards.

Until we address this imbalance we will continue to be hounded by populist politicians profiting from fear and hate. The longer we ignore the problem, the more powerful will be our reckoning. This devil will have his due.