Here’s the question — do walls work?
When asked that question, two examples popped up in a Google search, the Great Wall of China and the Berlin Wall.
China’s wall was started during the Ming Dynasty and stretches just more than 5,000 miles through picturesque but rugged terrain. Scientists in the 1700s guessed the wall was so big it could be seen from the Moon, which turned out not to be the case. However, when mankind began orbiting Earth, it could be seen from a decent distance.
The Berlin Wall was a relative piker compared to the Chinese barrier, separating East and West Germany for a little more than 100 miles. The German barrier didn’t have the legs of the Chinese version, being built in the early 1960s. The barrier was officially opened in November 1989, and destruction began in June 1990, with exuberant partying occurring on both sides.
The two walls differ in many ways. The Great Wall version was ostensibly to keep marauding hoards of nomads out of China. The Berlin version was to keep Communists on one side, and non-Communists on the other side. Both were relatively effective with regard to their original design principles.
However, even the Great Wall didn’t stop all the invasions, and individuals popped back and forth across the wall with alarming regularity. The same was true for the Berlin Wall, as Germans kept slipping through, over and under the wall to visit friends and relatives on the other side.
So, the short answer about walls’ efficacy is that, yes, they can and do keep people out or in, depending on purpose. They are most effective in dense urban areas, where humans and electronic devices can monitor movement.
With regard to the “Great Wall” in President Trump’s campaign promise, the lack of effectiveness is not in question, at least to experts in these matters.
The border between the United States and Mexico is 1,954 miles, from the Pacific Ocean in California to the Gulf of Mexico in Texas, about 600 miles of which, give or take, has fencing, walls and various barrier devices.
Given the fact that so much of the border has no barriers, other than natural obstacles — of which there are many — the notion of walling off the United States from its southern neighbor seems preposterous.
In rural settings such the U.S./Mexico border, walls are functionally ineffective. To breach them requires a ladder or a shovel. And out where literally no one is watching, except the border crossers, one can take his or her time setting the ladder, going up one side and climbing down the other.
This concept may explain why there aren’t walls all over the world’s socio-political trouble spots. Generally speaking, walls are incredibly expensive and usually don't stop people from crossing borders at will.
Another issue with a solid concrete wall, other than sheer inefficiency, is called “opacity,” which boils down to border agents not being able to see what’s happening on the other side, and thus not having the information necessary to make wise decisions. Steel bars make more sense in that context.
A former Border Patrol spokesperson has called the existing fence little more than “a speed bump in the desert.” A solid wall could conceivably make things exponentially more difficult for Border Patrol officers.
Another factor against such a wall is that about a third of the immigrants in this country illegally entered on a legal visa, then decided to stay when the visa expired.
We won’t argue with the president’s zeal for better border security, but spending billions on a all-but-useless wall is the wrong way to go.