This is a column about Martin Luther King’s other dream.

His most famous dream, of course, is the one he articulated at the Lincoln Memorial in 1963. It was a vision of racial amity so frightening that people killed to keep it from coming true. Five decades later, it’s so broadly accepted that even those who don’t believe in it feel constrained to pretend they do.

But King’s other dream is as controversial now as it was back then.

See, it was a dream of economic justice wrought by a rainbow coalition of the dispossessed. King thought that if you could pull together the poor blacks of the inner cities, the poor American Indians of the reservations, the poor Latinos of the barrios and the poor whites of Appalachia, if you could get them to put aside their differences and unite around the meagerness and exploitation they all had in common, you’d have the makings of a movement that would break the old paradigms.

King had in mind nothing less than radical transformation, musing about “a democratic socialism” and arguing for a guaranteed income and a “Bill of Rights for the Disadvantaged.” “True compassion,” he wrote, “is more than flinging a coin to a beggar; it understands that an edifice which produces beggars needs restructuring.”

But King was murdered in Memphis 49 years ago this week, and that other dream was left orphaned. It has lain largely forgotten ever since.

So it was welcome news that the Movement for Black Lives, a coalition of groups demanding African-American “power, freedom and justice” and the Fight For $15, a group advocating for worker’s rights and a living wage, had joined forces to commemorate the assassination with marches in Memphis and around the country. We can only hope this is not a one-shot deal. We can only hope it is the start of a permanent movement.

No one should want that more than the white underclass.

Ever since they waded into cannon fire to protect the right of rich people to own black people, poor white people have, in the aggregate, been victims of the longest con in American history. Monied interests have used race to disadvantage them time and again.

They accepted the fool’s gold of racial superiority, the lie that black or brown poverty proved black or brown laziness. Yet they could not ask for wages enough to live on for fear those “lazy” blacks and browns would be brought in to do the work for less.

Still, they consoled themselves that they had nothing in common with those “other” poor, even as their schools crumbled, children’s bellies rumbled, wages stagnated, buying power deflated, and jobs went away. They clung to the notion that theirs was somehow a higher class of indigence, a nobler species of destitution. Because they were white.

Never mind that you can’t pay the electric bill with “white.”

Forty-three million Americans live below the poverty line; 28 million of them white. The black poverty rate is a staggering 24.1 percent. Meantime, the rich get richer, and a man in the millennial generation has only a 50 percent chance of earning more than his folks did, according to a study by a team of economists led by Stanford professor Raj Chetty. A baby boomer was almost certain to do so.

So a movement combining Martin Luther King’s twin dreams would be a welcome and overdue recognition of the obvious. When it comes to racial and economic justice, the idea that we can fight for the one while ignoring the other is delusional.

If you don’t have both, you don’t have either.

Leonard Pitts Jr. is a columnist for The Miami Herald. He can be contacted at:

lpitts@miamiherald.com