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Story highlights

Trump is asking congressional Republicans, not Mexico, to fund the plan with taxpayer money

As Trump noted, the Great Wall of China runs more than 13,000 miles

(CNN) —  

Now that he’s about to assume office, the real costs of the “great, great” wall Donald Trump promised to build during his campaign are beginning to settle in – and threaten to divide the President-elect and thrifty Republicans on Capitol Hill.

But Trump’s grand vision of a impenetrable barrier from the Pacific Ocean to the Gulf of Mexico – a physical monument to his hardline immigration policy – hasn’t dimmed, although some of the specifics have changed.

He is asking congressional Republicans, not Mexico, to fund the plan with taxpayer money through the appropriation process. As for his pledge to have Mexico foot the bill, Trump in a tweet Friday morning claimed “that any money spent on building the Great Wall (for sake of speed)” will be reimbursed down the line.

Trump rarely shies away from superlatives and yet, his mention of a “Great Wall” invoked images of another very lengthy, defensive superstructure – one he’s had on his mind for a while.

“You know, the Great Wall of China, built a long time ago, is 13,000 miles,” Trump said in 2015. “I mean, you’re talking about big stuff. We’re talking about peanuts, by comparison, to that.”

But the differences don’t end there. Here’s how the President-elect’s would-be border fortress stacks up against its Chinese competition.

One is much longer than the other

As Trump noted – accurately – the Great Wall of China runs more than 13,000 miles. According to a recent survey by China’s State Administration of Cultural Heritage, it spans 15 provinces, autonomous regions and municipalities. The US border with Mexico, meanwhile, touches only four states – California, Arizona, New Mexico and Texas. There are currently 700 miles of fence along that track, with another approximately 1,200 miles either open, nearly impossible to actually build on or impassable.

One was built by warriors, conscripts and criminals

In China, different dynasties employed varying methods of construction. But the process was uniformly dangerous and unknown thousands of builders died in accidents and from overwork and exhaustion. Soldiers were employed at the very start, but over the centuries, criminals and conscripts did much of the work.

Trump has not made clear who will handle construction now, though a number of private contractors, including the firm that built a border wall in Israel, have suggested they could seek the job – and a lot of taxpayer money.

One was overseen by dozens of rulers over centuries

If Trump can appropriate the funds he needs to start up construction again, the US project will have spanned parts of three presidential administrations. The Chinese process went on much longer, with dozens of rulers overseeing long periods of construction, followed by centuries of quiet, decay and, with the onset of a new dynasty, revamped efforts to repair and expand the great wall.

China did get a bit of a head start. In 221 BC, the first Qin emperor unified the country and merged previously erected barriers, meant to protect the states from each other, to form an outward-looking wall. They built for a decade straight as the evolving nation sought to protect itself from nomadic tribes to its north. For centuries, new wall came up in fits and starts. The Ming Dynasty, which ruled from 1368 to 1644, added approximately 5,000 miles.

The American border barrier, mostly fence, was approved by Congress and signed into law by President George W. Bush in 2006. There are currently 700 miles of fence spanning the southwest border with Mexico.

One faced enemy armies

The Chinese spent centuries using the wall as a means of defending their land and culture from nomadic tribes, Mongol raiders and other political enemies. During the rule of the Mongol Yuan Dynasty, at first led by Genghis Khan in the early 13th century, the wall was mostly used as a trading outpost and to help the ruling government put down rebellions.

In the US, the political movement behind Trump’s “build the wall” pitch is mostly concerned with illegal immigration – even as the number of unauthorized Mexican migrants has diminished – and drug cartels.