× Expand Landesarchiv Berlin Martin Luther King, Jr., at the Berlin Wall (Bernauer Straße at Schwedter Straße) on September 13, 1964, with Werner Steltzer, the director of the Berlin Information Center.

With the national government held hostage by President Trump’s insistence on a wall along the U.S.-Mexico border, it is appropriate, as we approach Martin Luther King Day, to recall the Reverend Dr. King’s views on the efficacy of erecting walls to separate human beings.

We don’t typically associate Dr. King with the fight over immigration in America because, as Obery Hendricks has observed, it was not an issue he was vocal about—although proponents on both sides of the issue have sought to invoke his memory to support their cause.

But we can glean much about his likely position from a pair of speeches he delivered in September of 1964 to audiences on both sides of one of history’s most infamous walls, and a symbol of the Cold War, the Berlin Wall.

That wall had been constructed just three years prior at an estimated cost of $25 million, over $200 million today. Its purpose was to physically separate the citizens of East and West Berlin, and to bulwark the ideological divide between a communist state to the east and a democratic one to the west.

Invited by West Berlin Mayor Willy Brandt to address the city at its 14th Annual Cultural Festival, King spoke to some 20,000 West Berliners at the Waldbühne Amphitheater. While there, King received news of an East German man struck by several bullets as he attempted to escape to the west. In response, King asked to visit the wall. Despite reluctance on the part of U.S. authorities, who took away his passport, King was allowed to pass through Checkpoint Charlie with only a credit card for identification. This was perhaps because communist propagandists saw an opportunity to exploit the U.S.’s shameful record of racism by welcoming a black civil rights proponent to speak. King proceeded to give the same address to an audience of some 2,000 East Berliners packed in at Marienkirche (St. Mary’s Church).

King’s remarks dwelt on the absurdity of the barricade. “No man-made barrier can obliterate” the fact that “God’s children” reside on both sides, he said. “There is no East, no West, no North, no South, but one great fellowship of love throughout the whole, wide world.”

“Wherever reconciliation is taking place,” he added, “men are ‘breaking down the dividing walls of hostility” which separate them from their brothers, there Christ continues to perform his ministry.”

Dr. King spoke to the East Berliners about the strategies and tactics of the nonviolent Civil Rights movement, recounting the work of the struggle for Black Freedom, and introducing the audience to activists like Rosa Parks. While not explicitly calling East Berliners to resist their oppressors, his words illuminated the possibility of mass mobilization from the grass roots, and the power of reform based on human dignity and compassion.

So, what would Martin Luther King think of Donald Trump’s plan to spend $5.7 billion dollars, for starters, on a border wall? Most likely the same message he delivered to those living in the shadow of the Berlin Wall.

“Regardless of the barriers of race, creed, ideology, or nationality, there is an inescapable destiny which binds us together,” King said. This “common humanity,” he concluded, “should make us sensitive to the sufferings of one another.”

If the President succeeds in the construction of his wall, it will surely become known, as the Berlin Wall was, as the “Schandmauer” or Wall of Shame, a physical reminder of our denial of human dignity.

When we lose the capacity for such sensitivity and seek to erect vainglorious barriers, we stray not only from the principles of our democracy but from the foundations of our shared humanity. The shooting that compelled King to ask to visit the wall came out his sense of compassion, something much needed today in light of the mass internments, separation of families, and death—most recently of two children—created by Trump Administration policies.

If the President succeeds in the construction of his wall, it will surely become known, as the Berlin Wall was, as the “Schandmauer” or Wall of Shame, a physical reminder of our denial of human dignity. In their shallow victory, Trump and his supporters will betray the larger principles of our democracy, and ignore more cost-efficient and humanitarian alternatives that constitute sane immigration reform while sustaining our national values.

Today’s opponents of walls can draw inspiration from King’s words. “Whether it be East or West,” he said, “men and women search for meaning, hope for fulfillment, yearn for faith in something beyond themselves, and cry desperately for love and community to support them in this pilgrim journey.”