An activist holds a Martin Luther King Jr. sign during a on Jan. 18 in Chicago. (Scott Olson/Getty Images)

IF ASKED to set a date for the beginning of the modern civil rights movement, most Americans would point to 1955, when a young, inspiring preacher named Martin Luther King Jr. helped turn a local protest into a national cause. The refusal of an African American woman named Rosa Parks to give up her seat on a bus in Montgomery, Ala., set off a citywide transit boycott and triggered years of demonstrations for racial equality across the South that, thanks to the new medium of television, caught the nation’s attention and its conscience.

When he led that protest in Montgomery, King had less than 13 years to live, and even before his death, his ministry to the nation was being disparaged by new voices of black nationalism as well as those on the other end of the scale who deplored his views on the war in Vietnam, which was tearing the country apart. But his legacy survived all this, and in recent decades it has grown, taking on new relevance for our country in the midst of a presidency under which the rules of respectability and regard for human dignity expected of a nation’s leader have been repeatedly broken, with the acquiescence, if not outright support, of many of the president’s colleagues and supporters.

King was a world figure, and he acted and thought accordingly. He knew that while the oppression and exploitation of black Americans was a product of this country’s unique history, there were many places in the world where the forces that produced such evils were never far below the surface. “Our age is one in which men have turned away from the eternal God of the universe and decided to worship at the shrine of the god of nationalism,” he said in a sermon in 1953. “We are all familiar with the creed of this new religion. It affirms that each nation is an absolute sovereign unit acknowledging no control save its own independent will. . . . Will we continue to serve the false god that places absolute national sovereignty first, or will we serve the God in whom there is no east nor west?”

King was a young man when he delivered that sermon, but he did not live long enough to see the new eruptions of nationalism in our own time, some based on race and ethnicity, others on chauvinism and fear. Today we hear much talk of national “sovereignty,” an old and honorable-enough concept that can be, and often is, perverted into horrible abuses. Just ask the Rohingya of Myanmar, also known as Burma, hunted and killed by their sovereign rulers, or the thousands fleeing the republic of Venezuela, whose government answers to no one as it goes about destroying the national society and disrupting an entire region. Meanwhile, repressive powers such as China and Russia regularly respond to objections over gross human rights abuses by decrying interference in their “internal affairs,” and these days they get little resistance from our own America-Firsters.

To judge by his words, King would see such authoritarian rulers for what they are, just as we should today, because he knew their types well: the ones who ruled by setting one class or race or nationality against another; who told those at the bottom to just mind their manners and know their place and they’d be fine; the ones who complained about “outside agitators” stirring up trouble. King felt there was a need in his time for prophetic vision in public life. The need is even greater now, the vision as clouded as it has been in a long time. This day should bring at least a moment of clarity.