Somehow, ancient China was able to do what America cannot: seal off its border, and at far greater expense and effort than it would take the United States.

The Great Wall of China has been measured at 13,173 miles, about 6.7 times the size of the fence that would be required to seal the U.S. Mexican border, which is 1,969 miles long.

What’s more, the Great Wall was vastly superior to anything being contemplated by the United States, having been constructed not just to keep foreigners out, but to withstand attack. And some of it was built over hilly terrain far less accessible than the flat desert that separates the United States and Mexico.

Republicans, who insist on sealing the border before considering amnesty for those who have entered the country illegally, are hardly demanding something unprecedented and technologically unachievable.

Nevertheless, the Obama administration has been seeking to minimize the need for border security and inflating the facts about how much of the border has already been sealed.

“Too often the border security refrain simply serves as an excuse,” Department of Homeland Security Secreatary Janet Napolitano alleged during a Senate hearing last month. “Our borders have in fact never been stronger.”

Thickly layered – it can be seen from low orbit earth – the Great Wall of China was laboriously piled together with earth, stones, wood, and brick, and it includes thousands of towers, wall platforms, stone pits and houses to ensure it was well monitored.

By contrast, a mere 651 miles of fencing has so far been “completed” on the Mexican border – and that’s under a very loose definition of “fence.”

According to Politifact, this includes only 352 miles of “pedestrian fencing” that would keep out those trying to run across. Another 299 miles is “vehicle fence” which “would be more accurately described as posts placed close enough together that cars can’t be driven between them.”

What’s more, only 36.3 miles of fencing are “double-layered,” as called for under the Secure Fence Act of 2006, which required all of it to be reinforced in this manner.

Though centuries old, miles of Great Wall fortifications even today remain more imposing than what the United States is trying to construct to stem illegal immigration.