The Rev. Martin Luther King Jr. was not assassinated at a rally organized by a right-wing talk radio host, or at the inauguration of a conservative Republican governor.

King, the Nobel Peace Prize-winning campaigner for economic and social justice whose legacy we celebrate with a holiday that falls on Jan. 17 this year, died while supporting the right of public employees to organize labor unions and to fight for the preservation of public services.

That inconvenient truth is sometimes obscured by pop historians, who would have us believe that King was merely a "civil rights leader." King's was a comprehensive activism that extended far beyond the boundaries of the movement to end segregation. His most famous address, the "I Have a Dream" speech, was delivered at the 1963 "March on Washington for Jobs and Freedom" — a historic event that explicitly linked the social and economic demands of campaigners for civil rights and economic justice.

And King always saw that linkage as being well-expressed — arguably best expressed — in the struggles of public employees and their unions for dignity, fair pay, fair benefits and a recognition of the contributions made by those who collect our garbage, clean our streets, police our communities, protect our environment, care for our aged and infirm family members, teach our children and deliver our mail.

It was to that end that King made his last journey, at the age of 39, to march with and campaign on behalf of members of the American Federation of State, County and Municipal Employees union in Memphis, Tenn., in April of 1968.

The sanitation workers of Memphis had experienced not just racial discrimination but the disregard and disrespect that is so often directed at those who perform essential public services.

No one should miss the fact that AFSCME, the union that they joined and the union with which King worked so closely, is now under attack by right-wingers who would have us believe that public workers are to blame for the problems that occur when policymakers blow the budget on tax cuts for the rich, bailouts for big banks and military adventures abroad.

King did not fall for the fantasy. He stood at the side of public employees, telling a Memphis congregation on the night before he died: "Let us keep the issues where they are. The issue is injustice. The issue is the refusal of Memphis to be fair and honest in its dealings with its public servants, who happen to be sanitation workers. Now, we've got to keep attention on … the fact that one thousand, three hundred sanitation workers are on strike, and that Memphis is not being fair to them."

King was proud to rally with public workers, and proud to make the connection between their struggle and the broader struggle for a fair and equitable economy that served all workers — public and private.

The defense of public employees — so essential to a functional society, and yet so frequently abused by the powerful players who would diminish the role of government in order to enhance their own wealth and authority — is as vital a struggle today as it was in 1968.

As Gov. Scott Walker and his legislative allies target public employees for abuse, it is as necessary for the right-minded and right-hearted people of Wisconsin to defend those workers as it was for the right-minded and right-hearted people of Memphis.

King's call echoes now. "Let us rise up tonight with a greater readiness," he declared on the night before he was slain. "Let us stand with a greater determination. And let us move on in these powerful days, these days of challenge to make America what it ought to be. We have an opportunity to make America a better nation."