Construction crews are erecting eight looming prototypes of President Trump's border wall in a remote section of the San Diego borderlands. Four are solid concrete; four are made of steel and concrete; one is topped with spikes. They all approach 30 feet in height. Customs and Border Protection is paying $20 million to six construction companies from Mississippi, Maryland, Alabama, Texas and Arizona. Crews in white hardhats operating cranes and forklifts are expected to complete the models by the end of the month.

Once the sections of wall are finished, CBP — parent agency of the Border Patrol — will evaluate them for three criteria.

"We want a better barrier. One that is hard to scale, hard to penetrate and hard to tunnel under," says Roy Villareal, chief of the San Diego Border Patrol sector.

"We're hoping innovation from private industry combined with our experience generates the next evolution of border security infrastructure," he continues.

About a half-dozen undocumented immigrants have been apprehended in the middle of the construction since the concrete slabs started going up. Most of them hopped over the 10-foot, Vietnam-era landing mats that currently serve as the primary border fence. The Border Patrol says, typically, it picks up about 70 illegal crossers in the entire San Diego sector every day.

While the mockups are massive, it's anybody's guess whether they'll ever get built. Trump's border wall is opposed by congressional Democrats, as well as most of California's and San Diego's leadership. But they're certainly getting lots of press. Every day, border agents in crisp green uniforms shuttle in news crews from as far away as the Czech Republic and the Netherlands to shoot video of the busy construction site just east of the Otay Mesa port of entry. The backdrops: south of the prototypes is a dusty Tijuana industrial zone; to the north are the rugged Otay Mountains.

"The real issue with building a border wall is what the Congress does, not what the contractors do ... The price tag on this is enormous," says Doris Meissner, a former immigration commissioner and now a senior fellow at the nonpartisan Migration Policy Institute.

CBP expected the prototypes to spark big protests similar to the crowds that massed at the Standing Rock Sioux reservation in North Dakota last year decrying the pipeline. Officials even set aside a "free speech zone" and planned contingencies if trouble broke out. But since construction began three weeks ago, there have been no demonstrators.

"We knew this was political theater (from the Trump administration) and we're not going to respond," says Christian Ramirez, director of the Southern Border Communities Coalition in San Diego. "This is much ado about nothing." He says the much photographed prototypes represent "a guise that a border wall is being built" to please Trump supporters who chanted "Build the wall!" during the campaign.

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