At the Otay Mesa port-of-entry just east of San Diego, Marines top an existing border wall with another two rows of concertina wire. Through slats in the steel fence, 2nd Lt. Dustin Pavlick can see rows of semi-trucks queuing up on the Mexican side of the border. This is the young Marine officer's first deployment.
"We construct this wall," he says, when asked about his assigment. "Work on this wall and construct these obstacles and that's pretty much it, sir. That's our job. That's our mission and the mission has priority at this time."
Even though most of the Marines are from bases just a few miles away, they will be along the border during the Thanksgiving holiday.
Army Sgt. Eric Ziegler, a military policeman, is working at the nearby San Ysidro port-of-entry. He has been away from his wife before, when he deployed to Afghanistan.
"She's prior military so she understands if I'm gone somewhere else," Ziegler said. "Pretty much wherever the country needs you."
The Pentagon decided these Marines would be deployed unarmed. Ziegler and other Army MPs from Fort Bliss, who carry sidearms, are guarding the Marines as they install concertina wire around a pedestrian walkway on the San Diego side of the border.
The rules are that MPs are not supposed to engage anyone crossing the border, unless they or the Marines are under threat.
"We call Border Patrol and they come get them," Ziegler says. "We cannot legally handle them."
A non-lethal role for Marines
Marine engineers are laying miles of concertina wire, as they did last week when the Border Patrol wanted to close three traffic lanes at the San Ysidro port of entry.
Reducing the number of entry lanes is a way to harden the border, according to Customs and Border Protection officials. It also slows down traffic.
Rogelio Lirrios and his family were on a shopping trip to San Diego late Friday morning and waited to cross for more than two hours. He is not happy with the number of migrants arriving in Tijuana.
"It's a different situation. I think it's a lot of people with a different culture," he said.
U.S. troops have kept their distance from the border itself. Col. Kyle Ellison heads Special Purpose Marine Air-Ground Task Force 7.
Last week, when a few people climbed the border fences as television cameras rolled, he did not send his Marines to stop them. Instead, the Border Patrol sent a civilian contractor to reinforce that section of fence.
"It is ensuring that we don't put our Marines, soldiers and sailors in a law-enforcement type situation," Ellison said. "It's not their task. It's not what they're out here for. So if we're going to be in a position where that potential exists to put our young Marines and sailors in a bad situation, I don't do it."
Ellison's headquarters unit is set up in tents inside a Customs and Border Protection maintenance facility. And that's where they expect to spend Thanksgiving. Troops won't head home to their families. They can't even stop for tacos on the way back to their temporary bases.
"I'm not concerned about morale," Ellison said. "I'm not concerned Marines and soldiers will have their heads down on Thanksgiving. They'll get a meal. They'll get a meal with their brothers and sisters and get back out and do their mission the next day."
So far, the operation is schedule to run until Dec. 15.
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