*Originally published on February 28, 2020.

Historically, walls and fences have been frontline weapons in the perennial battle to delineate "here" and "there," as well as to define "us" and "them."

They may seem archaic, but Canadian journalist and author of Walls: Travels Along the Barricades Marcello Di Cintio says the 21st century has been a boom time for walls.

In the past two decades, walls have been deployed once again as the number of asylum seekers skyrockets around the world.

There are now border fences and walls in Europe that together measure more than six times the length of the Berlin Wall — 30 years after it came down. And U.S. President Donald Trump remains intent on building a wall on the country's border with Mexico.

Di Cintio spoke with IDEAS host Nahlah Ayed about the resurgence of walls, how they became a political arsenal — and why there are promises to build even more of them.

Here is part of their conversation:

Towards the beginning of your book, you say that, "Walls don't just divide us. They can make us ill. They can drive us mad." You go on to talk about various kinds of actual mental illnesses that people experience in the shadow of the Berlin Wall...

It was a fascinating bit of research that I found. There was an East German psychiatrist who lived in Berlin during the time of the Berlin Wall, and he noticed that his patients who lived in close physical proximity to the wall showed higher rates of psychological problems, high rates of depression, higher rates of alcoholism, there was more domestic violence in their homes — and he blamed the wall. He called it the "wall disease."

Di Cintio cites an East German psychiatrist who noticed that patients who lived in close physical proximity to the Berlin Wall showed higher rates of depression and alcoholism. (Fabrizio Bensch)

And he suggested the only cure for the wall disease would be to take the wall down. Now, this particular psychiatrist ... had escaped to Berlin by the time the wall did come down. He was in the United States by then. But other psychiatrists noticed that not only did the falling of the Berlin Wall result in this political and social release, but also an emotional one and a psychological one.

There was a euphoria that came with the crumbling of that wall, which was, I suspect, the cure for the wall disease. And I had the idea of the wall disease in mind as I travelled around the world looking at my walls because I saw different strains of the wall disease everywhere I went.... All the people that I met who lived next to the walls and these barricades expressed some kind of wall disease, some sort of psychological problem.

People still managed to find ways to scale, get through or around walls and fences. What does that say to you about the efficacy?

There's no wall that's been successful in keeping people in or out. Everywhere that I went, I met people who somehow managed to either go over, under or around. And that's always going to happen. That's happening on the U.S.-Mexico border every day and everywhere else, too.

Di Cintio says people manage to either go over, under or around the fence at the U.S.-Mexico border every day. (Gregory Bull/Associated Press)

What that says about the people who get over is that these are people who combine internal intelligence with desperation and they figure it out.

They can figure out ways over, under or around. It's remarkable the kind of strategies that are employed by migrants and wall crossers everywhere in the world. They can see the weaknesses. They can figure it out. They'll hack those systems.

Do you think there's a difference in how those people see that wall (or that structure) because they don't actually see it, or does it become a wall in the mind?

Yes, and the wall in the mind is seen more positively than the wall in the eyes. The biggest opponents of these walls around the world are those people who live close to them. It happens in the United States, too, where people who live in states far from the southern border are far more pro-wall than people who have these things rising in their backyards in Arizona. And I think it's because the illusion is easier to digest. If you don't have to see the negative aspects of it, if you're far away from it, then what's the problem?

How is a wall a white flag or sign of defeat?

I think people put up a wall when they can't think of anything better to do. A wall is a symbol of failure. A wall is proof that we lack either the intelligence or the motivation to solve the problem. So instead of solving the problem, we throw up a wall as if we throw up our hands. And that's what I mean by being a white flag. It's a surrender to the problem: we cannot figure this out, therefore a wall goes up.

What is the political appeal of walls and fences in today's context?

They sell an illusion of strength and they sell a clear definition of difference. I'm building a wall because we, on this side, are the good people and we are inherently different from those on the other side. And that's an incredibly attractive notion, sadly, around the Western world these days, is that keep the bad away from the good. And we would define our differences through this very obvious physical barrier you can go and touch with your hands if you want.

This Q&A has been edited for clarity and length.

Guests in this episode:

Marcello Di Cintio — Walls: Travels Along the Barricades (Goose Lane, 2012), Pay No Heed to the Rockets: Palestine in the Present Tense (Saqi Books, 2018), Poets and Pahlevans: A Journey Into the Heart of Iran (Vintage Canada, 2006), Harmattan (Insomniac Press, 2002)

* This episode was produced by Nahlah Ayed and Philip Coulter. It is part five of our series, Walking the Border: Walls that Divide Us.