Once upon a long time ago, a tired man faced an audience of public workers. They were on a wildcat strike, demanding the right to bargain collectively and to have the city for which they worked automatically deduct union dues from their paychecks. The city’s conservative mayor had flatly refused these demands.

“You are doing many things here in this struggle,” the tired man assured them. “You are demanding that this city will respect the dignity of labor.” Too often, he said, folks looked down on people like them, people who did menial or unglamorous work. But he encouraged them not to bemoan their humble state. “All labor has dignity,” he said.

On Monday, it will be 43 years since that man was shot from ambush and killed in Memphis, Tenn. Martin Luther King’s last public actions were in defense of labor and union rights.

One wonders, then, what he would say of Wisconsin.

Or Indiana, Ohio, Michigan, Florida or any of the other places where, like a contagion, the move to weaken or effectively outlaw unions has spread. One wonders what he would make of a conservative governing ethos that now defines public employees — teachers, police officers, firefighters — as the enemy.

Actually, we need not wonder what King would have said, because he already said it. In the speech quoted above, he warned that if America did not use its vast wealth to ensure its people “the basic necessities of life,” America was going to hell.

The Baptist preacher in him reared up then, and his voice sang thunder. For all the nation’s achievements, he roared, for all its mighty airplanes, submarines and bridges, “It seems that I can hear the God of the universe saying, ‘Even though you have done all that, I was hungry and you fed me not. I was naked and you clothed me not. The children of my sons and daughters were in need of economic security and you didn’t provide it for them.’ ”

It will come as a surprise to some that the civil rights leader was also a labor leader, but he was. He had this in common with Asa Philip Randolph, who suffered long years of privation to establish the Brotherhood of Sleeping Car Porters. And with Walter Reuther, brutally beaten when he organized sit-down strikes that helped solidify the United Automobile Workers. And with Crystal Lee Sutton, inspiration for the movie “Norma Rae,” who lost her job for trying to unionize a textile plant in Roanoke Rapids, N.C.

These people and many others fought to win the rights now being taken away.

Granted, those rights have sometimes been abused — used to shelter the incompetent or reward the greedy.

But to whatever degree our workplaces are not filled with children working adult hours, to whatever degree an employer is required to provide a clean and safe workplace, break time, sick time or fair wages, that also reflects organized labor’s legacy.

It is instructive that this campaign to roll back that legacy is contemporaneous with a New York Times report on how General Electric earned $14.2 billion in profit last year, yet paid no U.S. taxes. Indeed, the Times says, GE netted a tax benefit of $3.2 billion.

What’s it tell you that some of us are on the offensive against working people, but breathe scarcely a peep when a giant corporation somehow slips through government-provided loopholes, paying no taxes? If need is a character flaw, what, then, is greed?

In some sense, we have traveled 43 years forward to get back to where we were in 1968. King would doubtless find that sobering. One is reminded of the axiom about those who will not learn from history. One is reminded of the quote about the price of freedom.

And one is reminded of a song Billy Preston sang in the summer of 1973. “Will it go round in circles?” he asked.

Apparently, it already has.

Leonard Pitts Jr. is a Miami Herald columnist.