By Kathy Hughes

Contributing Writer

 Is it time for another wall? The Great Wall of China and Hadrian’s Wall were built to keep intruders out. The Berlin Wall was built to keep the people in. Most European cities in the Middle Ages were surrounded by walls; settlements in frontier America were protected by stockades.

The Chinese Wall was built over centuries, but was begun between 350 and 320 BC. Certainly, walls were built before that time, but parts of this one survive until the present day, and it is the only human construction visible from space. It has been estimated that, in today’s money, it cost over $16 billion to build the full 13,000-plus miles, at about a million dollars per mile. Again, the construction costs should be amortized over the centuries it took to build it, so the costs per year would be much less.

Perhaps the greatest wall in western European history is Hadrian’s Wall, built around 120 AD by the occupying Roman army along the 70-mile border between England and Scotland. Since under Roman rule, the area’s great forests had been destroyed, the wall had to be built of stone imported at great cost from outside the immediate area. At an estimated cost of $200,000 per mile to build over a period of six years, the costs of maintaining and guarding the wall were partly responsible for abandoning it only 25 years later.

The bleakness of life for soldiers garrisoning the wall was expressed by W H Auden’s poem:

“Over the heather the wet wind blows

I’ve lice in my tunic and a cold in my nose.

The rain comes pattering out of the sky

I’m a Wall soldier; I don’t know why.

The mist sweeps over the hard grey stone

My girl’s in Tungria; I sleep alone…”

The lessons of history then tell us that walls may be effective, but are quite expensive not only to build, but to maintain, and the border still must be guarded to some extent. The US border with Mexico is over 2,000 miles long, and covers inhospitable terrain. The Panama Canal cost about $375 million, which may be a good comparison to building a Mexican Wall, but even then in today’s money is a couple billion dollars. The aesthetics probably are not even a consideration, so we’re probably facing a concrete wall, topped with barbed wire — something like the Berlin Wall, perhaps.