Martin Luther King Jr., second from right, is shown on the balcony of the Lorraine Motel in Memphis on April 3, 1968, the day before he was killed there. (Associated Press)

Every nation has sacred places, where history has stopped and lingered, and visitors are hushed by memories of redemptive sacrifice. One is the balcony outside Room 306 at the Lorraine Motel where Martin Luther King Jr. was assassinated. On this spot a familiar voice was stilled, but also somehow magnified, becoming part of our collective conscience.

This site is now part of a fine museum — the National Civil Rights Museum — that unfolds the story that King told and shaped. How 12 million Africans were shipped as slaves across the Atlantic, the largest forced migration in history. How they built resilient institutions that maintained their identity and demanded their freedom. How a great war ended slavery but not oppression. How African Americans suffered a century of cruel and systematic indignity.

Then came a movement of conscience in which being a community organizer could demand the courage of a soldier and get your head cracked open. A movement opposed by domestic terrorists who bombed homes and churches, and murdered children. (Should we refer to them as “radical Christian terrorists”?)

This story of a captive people who forced the United States to fulfill its own ideals — the story of prisoners who freed themselves and also freed their jailers — is one of the most compelling moral narratives outside of scripture. Leaders such as King believed that history has an arc, determined by the appeal of freedom and the Author of freedom. And their vision of human rights became an inseparable part of the American story: a nation that declared high ideals, then was judged by them, and now is motivated by them to expand the circle of inclusion, protection and promise.

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I happened to visit the National Civil Rights Museum at the same time that a presidential candidate was attacking the mother of a fallen American soldier by employing an anti-Muslim stereotype (“maybe she wasn’t allowed to have anything to say”). Donald Trump went on to assert that the soldier’s father, Khizr Khan, had “no right to stand in front of millions of people and claim I have never read the Constitution” — a statement that proved Khan’s point.

My point here is not that Trump is a classless, egotistical sadist — though that case is strong. It is that Trump’s view of nationalism is based on culture, ethnicity and exclusion. It does not even matter if suspicious outsiders have made what Abraham Lincoln called “so costly a sacrifice upon the altar of freedom.” Their faith, in Trump’s view, is foreign and immediately associated with stereotypes of oppression and violence. The same is true with Mexican ethnicity, which Trump has identified with sexual aggression and murder. Trump is not merely indifferent to the language of racial and religious inclusion; he is actively hostile to the premise.

Leaders who support Trump — members of Congress, conservative thinkers, figures of the religious right — do so for a variety of reasons. But whatever their motivations, they are encouraging an alternate and degraded version of the American story. In Trump’s telling, this is a nation that was once great but is now besieged and infiltrated by threats to its identity. Other nations — “France is no longer France” — have allowed their distinct cultures to be overwhelmed by immigration and outside influences. The United States must be protected from the same fate by a strong leader. And Trump’s America is defined as the familiar nation of decades past, which was largely white and Christian.

In fact, the United States is the model for the world when it comes to integrating Muslims and people of other faiths into a pluralistic society. Rather than recognizing this achievement, Trump would undo it and foster the kind of conflict he warns against.

But there is even more at stake. Those who support Trump are setting the Republican Party at odds with the American story told by Lincoln and King: a nationalism defined by striving toward unifying ideals of freedom and human dignity. Is this what the speaker of the House, the Senate majority leader, the chairman of the Republican Party and so many other good people intended when they entered politics? Is this how they define their soul’s high purpose?

In his last public address, the night before his murder, King mused on mortality, saying that he would die “happy” and “not fearing any man” because he was sure of his life’s mission, which included “standing up for the best in the American dream.”

Which Republican leaders can now rest in that confidence? It is not too late to repudiate.

The Fix breaks down the 10 Republicans who have been most vocally opposed to Trump's nomination. (Peter Stevenson/The Washington Post)

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