Borders are a substitute used by less fortunate lands for the sea and the mountains behind which happier countries shelter. No great civilization has grown and endured except behind the shield of ocean, mountain, or desert.

How different Poland’s history would be if it had a few dozen miles of deep salt water between it and its neighbors. How much trouble might be saved if Israel were an island. Countries with cliffs and churning, white-flecked seas for borders tend not to be partitioned or carted off into captivity, especially if they have the sense to build navies.

It is considered impolite to mention it these days, but Britain’s defiance of Hitler in 1940 owed more to the Channel and the North Sea than it did to the RAF. Salt water was our ultimate weapon, and our sensible respect for it made us hesitate, to Stalin’s fury, to launch any invasion against Hitler’s coastline. D-Day was a very near thing, even with the vast resources, the careful preparation, the brilliant deception. If the weather forecasters had gotten it wrong, the invasion fleet would have been scattered and the Red Army would have liberated Paris sometime in 1946, before driving on to the English Channel to ponder the future. At least it would have stopped there. 

People in free countries should be more in love with the sea, more sympathetic to those who don’t have it. I grew up in a Britain where every road ended at the sea. In fact, the sea lay just beyond the bottom of our garden in the Portsmouth suburb where we lived, endlessly reassuring especially when (as was usually so) it was rough or hidden by fog. As a naval family, we always remembered Lord St. Vincent’s witty promise to Parliament while Napoleon Bonaparte’s Grand Army gazed out toward England from the hills above Boulogne in France: “I do not say they cannot come,” St. Vincent creaked. “I only say they cannot come by sea.” Honorable members obediently laughed. For the British Navy controlled every square inch of those gray waters, and gaze as they might toward the coast of England from the parade grounds of Boulogne, the French could not cross them.

If a country has no sea, it must come up with a substitute. And that substitute is the guarded border. As a safe Englishman, I have never resented or decried these odd and often expensive structures. I can quite see why people want them. I can, alas, even envisage borders growing up in our own islands, where old nations are seeking to be reborn. There are worse things we might face. I have always thought that the French Maginot Line, now a derided ruin like the Great Wall of China, was rather sensible, its only fault being that it was unfinished, a major failing in any wall. I have helicoptered above much of the length of Israel’s frontier with the “occupied territories,” and indeed climbed through a rather feeble section of it in the Jerusalem suburbs, and I see the sense in it. No doubt it is often unjust, and it was much better for everyone when there was friendliness across the line and thousands of Arabs used to travel peacefully and easily to work in Israel. But the barrier is a reasonable response to the nasty tactic of sending suicide bombers into Israeli towns, as is shown by the fact that it has much diminished these horrible attacks. My only worry is that it cannot possibly be sustained. Walls, unlike oceans, require ceaseless maintenance and repair, and must be manned night and day by alert and disciplined guardians. Otherwise they become relics.

Israel is an interesting case. Turn eastward and you can, with some persistence, cross into officially friendly Jordan, just over the surprisingly feeble and narrow river of that name. This gateway is supposed to be part of the “New Middle East,” an absurdly optimistic concept dreamt up by the late Shimon Peres and based on the idea that Muslim Arabs would stop hating Israel if it made concessions to them. Very few people take the sort-of-bus service that runs from Tel Aviv to Amman, via Beit She’an—and no wonder. The Jordan River crossing on a Sunday evening is one of the loneliest places I have ever been, the sort of spot where you can hear yourself breathing, and the border officials hugely outnumber the travelers. The only other sound is the squeak of Israeli drivers unscrewing Hebrew license plates from their cars and substituting Arabic ones. This is an essential safety measure in Jordan, where the “Anti-Normalization League” campaigns ceaselessly against any concession to Zionism. Despite the country’s official moderation, it would not be a good idea to be identified as an Israeli on the country roads which wind down toward Amman. I saw no Jordanians crossing into the Zionist entity bent on pleasure or business. Normality is not just a fiction but an absurdity. Mr. Peres’s “New Middle East” is a phantasm, like the Arab Spring. The place only exists for propaganda purposes. In truth, the Jordan Valley remains a place of unalterable tension, and it is a pity that the river is not deep and wide, as the song says it is.

Travel up beyond the Sea of Galilee, past blasted concrete buildings and abandoned fortifications from the bitter war of 1973, and into the Golan Heights, where you will find a more honest frontier that is wholly dead and sealed, like a tomb. There is no pretense of friendship or normality here. Even so, when I asked an Israeli Army officer if he felt threatened, he remarked that it was one of the quietest places anywhere on his troubled country’s disputed edges. President Assad’s ruthless despotism left no doubt about who was responsible for any missiles or armed groups which came across it. “If anything bad comes across, we have a return address,” he pointed out, with quiet menace. This is why many Israelis will be glad if and when Mr. Assad regains full control. A reliable tyranny on the far side of the barbed wire is far more reassuring and desirable than anarchy or the Arab Spring.

Why, then, do so many speak darkly of borders as unnecessary and undesirable? Enthusiasts for “free movement of peoples,” the type who can be found in revolutionary Marxist sects and in the offices of liberal capitalist organs such as The Economist, claim to believe that the absolute equality of all humans is violated by the idea of frontiers. The Bolsheviks believed that humanity is infinitely malleable and that class and education determine changeable human nature. The economic liberals simply think that open borders bring greater general prosperity by keeping labor costs down. In most cases, such people live remotely from the areas most directly affected by the large-scale migration they say they support.

In practice, they will take a slightly different view if too many people act according to their vision. The open borders of much of the European Union have been at least partly closed again in recent years, following Chancellor Angela Merkel’s utopian decision to welcome thousands of undocumented Middle Eastern migrants (some of whom may actually have been refugees from the Syrian war, but many of whom were economically motivated, as The Economist would want them to be). Sweden, once a country of relaxed liberalism, has found its politics bitterly transformed after trying to apply those beautiful beliefs in practice. The decision of several E.U. navies to offer a ferry service across the Mediterranean for migrants from Africa caused a similar revulsion from this idealism. Suddenly, France began patrolling its borders with Italy for the first time in years.

Even on those who in general accept their usefulness, borders have a paradoxical effect. Precisely because they guard us from straying into a different culture, we long to do so. Like Lewis Carroll’s Alice clambering through the looking glass, we yearn to know what is beyond the wire, and what lies on the other side of the mysterious wooded hills that are visible but not reachable. Sometimes it is just a wish to know what is beyond that door or down that corridor. Not being allowed to go somewhere or know something, as we have known since the Garden of Eden, can be the greatest temptation of all. 

felt this most powerfully—the mad instinct for crossing into the unknown—when at the Korean Demilitarized Zone, an exhilarating spot which (after many years of effort) I have now viewed from both sides. My first visit was from the South, in a press party accompanying Margaret Thatcher. All around was the peace of an unpolluted animal and bird sanctuary, thanks to the absence of man. Both sides competed by flying enormous flags of their rival nations, flags so huge that they ripped themselves to pieces in high winds. Just to the north, beyond the so-called “Bridge of No Return,” across which prisoners of war and the crew of the captured USS Pueblo had been released by the Communists, sat a fake village from whose empty concrete buildings eerie music drifted, supposedly demonstrating the happiness of its nonexistent inhabitants. I am not sure whom this was supposed to fool.

Strangest of all was that, for a few hundred yards, there was no fence. A line of scrubbed paving stones marked the border, once the most emphatic and angry contact between the two rival worlds of the Cold War. On one side, political and religious liberty, prosperity, rationality stretched onward and outwards. On the other, a vast dark planet of censorship, people shrieking slogans, parades, lies, and privation continued all the way to the middle of Germany. Now it is less of an ideological border—just a puzzling, dispiriting relic of a dead conflict, which nobody can find a way of dismantling. 

Much as people are said to be tempted to hurl themselves off cliffs and tall buildings, I was gripped with a crazy desire to dash across into the North, and wondered if members of the Communist delegation, close and clearly visible on the other side, were troubled by the same folly. Years later, I knew they must have been. For I traveled down from Pyongyang, through the North’s fortifications and propaganda lectures, and found myself ten feet from where I had been twenty years before, with nothing between me and the South but air—but such air, fizzing and crackling with danger. Is there anything more savage than hostility between peoples divided by civil war? Enemy nations do not even begin to contrive the pseudo-moral excuses which people of the same nation dream up for killing and hating each other. Yet still I longed to make that foolish, fatal dash, just because it was there.

I used to get a similar feeling near the Brandenburg Gate in Berlin. I now feel privileged that I saw Berlin many times in the days of the Wall, and penetrated through it at Friedrichstrasse Station to emerge in a place so different from its Western twin that it is still hard to believe it was so. Technically, it was only a political division. But East Berlin smelled different, had different colors, somehow a different light in the sky. The posture of the people was different. Above all, the purpose of everyday things in the Communist world was tinged with a second, less everyday purpose. I learned from my first voyages into this zone that this was the great distinguishing feature. Shops, opera houses, trains, museums, war memorials, newspapers all possessed a greater ideological purpose which completely transformed them, but which I was not allowed to know in full. It always seemed a small miracle when I succeeded in buying a meal, making a journey, or obtaining information. I felt I hadn’t really been meant to do any of these things. When I got back to the West, its obliging simplicity began to seem unsatisfactory. Where was the challenge?

Even if we could somehow construct a world where borders were not necessary for peace and security, could we really be happy without them? There is a joy in crossing from one place into another that we are robbed of by any effort to make all places one. I cannot be the only person who has developed an active joy in obtaining and using hard-to-get visas. People used to complain about Communist border checks. I didn’t. I positively liked these Ludmillas and Nastyas with their frazzled, bleached hair under severe peaked caps, glaring at my documents with patriotic zeal. Generally, they didn’t actually take that long, and it was possible, sometimes, to get the faintest ghost of a smile out of some of them before they whacked the entry or exit stamp (always in lurid green ink) onto my passport. Nowadays the Russian border officials are positively chatty. One rather beautiful passport checker in Moscow recently asked me, “Do you think Russia will ever be a normal country?” and creased up when I shot back, “I hope not!”

There is the Schengen Agreement’s abolition of European borders. If I can stroll unchecked (as I have) from Strasbourg in France to Kehl in Germany, or from Aachen in Germany to Vaals in the Netherlands, so can anyone else. What, then, is the point of my machine-readable, ultra-secure United Kingdom passport, obtained through severe bureaucracy? It goes deeper. When we study the dismal history of the European 1930s, isn’t Germany’s scorn for the borders of her neighbors one of the most striking things in the newsreels and the photographs? Grinning soldiers smash or sweep through the border posts of conquered or absorbed nations, tossing aside the striped poles that symbolized independence, the quiet existence of another way of doing things, a different language, a different coinage, and a different law. Didn’t we fight World War II at least partly to put those borders back, and allow those small nations to live once again undisturbed as they wished?

Yet all those borders once brushed aside by German tanks are now vanished. Travel down from Berlin to Prague, or Berlin to Brussels or Amsterdam or Vienna, on Europe’s swift new trains, and nobody will ask for your papers. I jolly well think they should. This isn’t just because untold numbers of migrants, having crossed the Mediterranean or the straits between Turkey and the Greek islands, are now roaming a borderless Europe. People are entitled to live differently if they want to. It makes them happy and proud. A world without differences would be a world without any true character or any true freedom, since the planet is far too big a community for people to be effectively unselfish in it. Without borders, we would dwell in a global parking lot. A reasonable love of where you live, its customs, landscape, language, and humor, is the basis for all other communal loves.

So I have never really seen why Donald Trump likes the idea of a proper border between the U.S. and Mexico. He doesn’t seem to me to be the kind of person who has that generous affection for the small, the local, and the particular which is the foundation of proper patriotism. But never mind. It is a good idea, if only for the following reason: How can the U.S. reasonably ask people such as me, from law-governed, civilized nations, who have no plans to stay, to submit to fingerprint checks and intrusive questioning at airports, if it simultaneously allows countless persons from who-knows-where to walk straight into the country, vanish for years—and then apply for and be granted citizenship on the grounds that it is too much trouble to do anything else? If you want to have a country, you have to decide who can come into it. If you don’t, won’t, or can’t, it’s not a proper country. President Trump, build up that wall!

Peter Hitchens is a columnist for the Mail on Sunday.

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