President Trump’s commitment to building a wall along the U.S.-Mexican border continues to polarize both Congress and bilateral ties with our southern neighbor. While Democrats argue walls don’t work and even many Republicans question the $21.6 billion price tag, both concerns are overwrought. While critics say there is no utility in a border wall, countries around the globe have come to rely on them.

Consider the latest: On Jan. 7, Turkey announced it had completed half of a more than 100-mile wall along its border with Iran in terrain far more difficult than the Rio Grande Valley.

Of course, the United States may not want to be like Turkey or Iran, both anti-American dictatorships with some of the world’s worst human rights records. But border walls exist in Africa, Asia, and even Europe and they are not simply the tool of dictatorships. Democracies, too, embrace walls.

Consider all the countries which have turned to walls to increase security:

  • India and Pakistan: The two nuclear powers, with 1.5 billion people between them, have fought four wars since 1947, and continue to face each other down in Kashmir, a territory both countries dispute. In order to prevent Pakistani terrorists from striking inside India, the Indian government built a series of fences and walls to keep Pakistani terrorists at bay. Had it not, it is quite possible that the two countries might be at war right now.

  • Morocco and Algeria: Morocco built a 1,700-mile system of berms, fences, and ditches to stop the Polisario Front, an Algerian-sponsored terrorist group, from infiltrating the Western Sahara. It took seven years to build, but the result was so effective that Algeria agreed to a cease-fire, ending the Western Sahara war that had raged since 1975.

  • Israel and the West Bank: The Israeli border wall — well, actually more of a fence in most places — remains hugely controversial because many journalists and United Nations officials condemn anything Israel does, no matter how much precedent exists outside Israel. But, Israel’s fence reduced terror attacks by more than 90 percent, something decades of diplomacy failed to do.

  • Cyprus: The irony of so many United Nations officials condemning Israel or Trump’s demands for a wall is that the United Nations itself built a wall dividing Cyprus in order to separate Turkish and Greek combatants. While Cyprus remains divided, the wall ended the fighting.

  • Northern Ireland: Against the backdrop of a decades-long terror campaign by the Irish Republican Army and Unionist violence, the British and government of Northern Ireland built several so-called “Peace Lines,” fences and walls up to 25 feet tall and sometimes running for miles to separate Protestant and Catholic neighborhoods.

  • Saudi Arabia and Yemen: While the Iranian-backed Houthi militia has launched missiles at Riyadh, why hasn’t it sent terrorists to conduct hit-and-run attacks in Saudi Arabia? The answer is easy. After a series of Yemeni attacks in the late 1990s, Saudi Arabia demarcated the border and built a 1,100-mile border wall.

  • Saudi Arabia and Iraq: After the Islamic State steamrolled through northern Iraq, Saudi Arabia scrambled to build a 600-mile border fence and ditch system stretching from Jordan to Kuwait. It worked.

  • Turkey and Syria: During the 1990s, the Syrian government supported the Kurdish insurgency inside Turkey. Turkey responded by reinforcing its border with fences and minefields. The result? Fifteen years of quiet. It was only after Turkey’s President Recep Tayyip Erdogan cleared many of the mines and loosened restrictions that security declined in both countries. Today, as a result, Turkey is building a new, fortified wall stretching more than 500 miles.

  • Kenya and Somalia: Over the last two years, Kenya has made good on its promise to build a barrier along its 440-mile border. It may not look like much — as between Israel and the West Bank, it is more barbed wire fence than concrete wall — but Kenyan authorities have said it has reduced infiltrations by Somali terrorists.

Of course, not all countries utilize walls for security. Many others use walls and border fences to prevent illegal immigration.

  • India and Bangladesh: Beginning in the 1980s, India began construction on almost 1,800 miles along its border with its neighbor. While India justifies the fence in its efforts to curb illegal immigration, they have also cut down cross-border crime.

  • Spain and Morocco: Spain has long maintained two enclaves — Ceuta and Melilla — on the Morocco side of the Strait of Gibraltar. Both are surrounded by high fences to keep African migrants out of Spain and therefore the European Union.

  • Greece and Turkey: The land border between the two countries is little more than 100 miles, but this is marked by barbed wire fences and, in places, minefields. While the mines are a vestige of military conflicts between the two countries, the European Union has been fine with them remaining to deter illegal immigration from the Middle East into Europe.

  • Hungary and Serbia, Croatia: Hungary isn’t shy about justifying its border fence in its desire to prevent illegal immigration by those originating outside of Europe. Greece’s land border may be well-defended, but African and Middle Eastern migrants simply make the first leg of their journey by sea, before moving north through the Balkans. Other European states might tolerate such a flow; Hungary sees no need. After all, migrants and asylum-seekers are supposed to remain in their first country of entry, which land-locked Hungary never would be.

Just because other countries have invested in walls and fences, of course, does not necessarily make them a panacea. But as debates in Congress once again turn toward immigration and the status of illegal (or, in politically correct parlance, “undocumented”) aliens, critics of the border wall are more uninformed than the president they dispute if they believe Trump’s proposal is inconsistent with international norms.

Indeed, every year, more countries resort to walls after more liberal policies fail.

Michael Rubin (@Mrubin1971) is a contributor to the Washington Examiner's Beltway Confidential blog. He is a resident scholar at the American Enterprise Institute and a former Pentagon official.

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