In retrospect, the Wall didn’t last especially long.

Twenty-eight years—roughly the span of our youth—and then it was gone: broken into chunks, carted away as souvenirs, placed on mantles and shelves, displayed like a trophy of some cherished victory we had all somehow won together. For those who needed additional reminders, the Wall was turned into refrigerator magnets and paper weights.

But how could we forget it? For nearly three decades, the Berlin Wall figured in our culture. Still just weeks old, the Wall became the stuff of made-for-TV movies and documentaries. Twenty-nine East Germans escaped through a tunnel that NBC financed in return for the rights to broadcast the escape. When television wasn’t big enough, the Wall leapt to the big screen. It played alongside Richard Burton, Paul Newman and Michael Caine, overshadowing them all with its screen presence. The Wall preened for magazine pictorials and played the heavy in spy novels. It turned Berlin into a bucket-list destination, as foreigners crowded to take photographs at Checkpoint Charlie and Potsdamer Platz. And its demise was spectacular—albeit in a cheesy, ’80s sort of way, broadcast live on MTV.

Thirty years after the opening of Berlin, the Wall lingers in our collective memory. Its physical remains—many stamped with an MTV logo—have been relegated to basements and attics. The refrigerator magnets slip and clatter across our kitchen floors, releasing their grip on grocery lists and coupons, but the Wall still shows up frequently in op-eds and political debates.

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When I was working on a book about the history of walls, the Berlin Wall was typically the only monument anyone asked about. Later, at lectures and book signings, I would show photographs of grander structures, ancient walls stretching over foreign horizons: The Romans had built hundreds of miles of walls, as had the Persians. So, too, the Chinese, the Mesopotamians, the Ukrainians, Danes, English, Peruvians, and dozens of other peoples. But it was always Berlin which that dominated discussion. The movies, television shows, spy novels and concerts had made sure of that. Or perhaps we cling to its memory because it seemed so damned simple, as if historical lessons were ever really straightforward.

What are we to make of a Wall that is no more? Something about impermanence, I imagine. The work of our hands never lasts. The Mesopotamians, who built a civilization out of sun-dried mud brick, knew that nothing lasted, and they knew that even when they constructed the world’s first historically-attested border wall, earliest ancestor to Berlin’s. The First Emperor of China forgot that truism. He spent his life in a vain quest for immortality, and the great tamped-earth walls which he intended to immortalize his empire eroded almost as quickly as they went up.

A wall, it seems, lasts only as long as the political will to maintain and defend it. The most successful walls stood for decades or even centuries until the state that supported them rotted from some cause or other. In Cold War-era Eastern Europe, the rot was economic, environmental, demographic, arguably spiritual. Rust triumphed over ideology. Hungary decided it could no longer afford the upkeep on its hundreds of miles of guarded and electrified barriers. With a vast section of the old Iron Curtain opening up, the Berlin Wall no longer made sense.

The ideologies that build walls and the ideologies that oppose them are no more enduring than the structures themselves. For nearly three decades, from 1961 to 1989, much of the Western world viewed the Berlin Wall as a symbol for the evils of Communism. Another 30 years have passed and that view of the Wall has been almost entirely forgotten. Today, the Berlin Wall is more commonly invoked in political debates as a symbol for the evil of all walls, the original ideology behind the Wall being completely forgotten or at least given a pass.

The 30 years since the end of the Wall have seen barriers arise on borders around the world. Only this time we can’t agree on what they mean. The walls around Israel have been hailed for their role in drastically reducing terrorism and reviled for segregating a region. The barriers on the southern U.S. border walls have been dramatically extended by recent presidents—Clinton, Bush, Obama and Trump—while politicians have performed acrobatic flip-flops in their positions on border security. Nowhere do we find the simplicity of Berlin, or at least what we once took for simplicity.

If there was a simple truth to the Berlin Wall perhaps it was this: that party bosses once tried to divide a nation that longed to be united. The Wall was always too weird, too unique, a monument to serve adequately as a symbol for all walls, but as a symbol for the willingness of political leaders to embrace division, it serves nicely, even if that lesson requires a little too much self-reflection to be popular. And so the Wall has been gone for 30 years now, and we continue to create our villains out of impermanent things and fleeting ideologies—rarely acknowledging that barbed wire rusts away, but political division regenerates and renews, dividing us more thoroughly than any physical barrier ever could.

Historians’ perspectives on how the past informs the present

David Frye is the author of Walls: A History of Civilization in Blood and Brick.

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