Probably the wall could be better for building tunnels cheaper. See-through walls should be better than solid walls!
1. The tunnels now can be starting near the high wall, hence tunnels can be now shorter and quicker to build.
2. The tunnels were built previously by paying to workers. Now tunnels can be built by volunteers.
When tunnels are built without having to pay labour costs. It's not only a big saving, but also unlimited number of tunnels can be built, all within a short time, also simultaneously!
Much much harder now to detect/stop hidden activities, due to possibly so many tunnels being planned concurrently! LOL
http://fourwinds10.com/siterun_data/history/american/news.php?q=1457372701
Immigrants hide from a border patrol vehicle while waiting for a chance to cross into the United States at the border fence on the outskirts of the Tijuana, on September 19, 2009. (7)
Soldiers prepare to enter a tunnel during a presentation to the media in Tijuana, on November 16, 2011. Police discovered a "major cross-border drug tunnel" running to California from Mexico, and seized 14 tons of marijuana, authorities said. The tunnel linked warehouses in an industrial park south of San Diego and the Mexican border city of Tijuana. (7)
Soldiers prepare to enter a tunnel during a presentation to the media in Tijuana, on November 16, 2011. Police discovered a "major cross-border drug tunnel" running to California from Mexico, and seized 14 tons of marijuana, authorities said. The tunnel linked warehouses in an industrial park south of San Diego and the Mexican border city of Tijuana. (7)
Although the existing U.S.-Mexico border fence has served to slow down the flow of drugs, criminals and illegal immigrants into the U.S., it is far from stopping it. The above photographs help us see that the existing border fence is inadequate to stop the illegal immigration and drug-human trafficking across our southern border. In order to achieve the kind of security all Americans citizens deserve, the existing fence must be replaced by either a taller, more secure double-fence with an high speed road in-between or an unscalable high wall with a high-speed road on the U.S. side.
In addition, counter measures must be constructed below ground to counter-act any and all tunneling under the fence or wall.
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