New roads built to facilitate drilling in southern Texas are also facilitating the movement of something else.

Energy companies boring into the depths of South Texas in the multibillion-dollar hunt for natural gas and oil are opening a growing fissure in U.S.-Mexico border security as they build hundreds of miles of private back roads and an uncharted pipeline to America for drug traffickers.

Hefty roads running through once-remote ranchlands now enable loaded-down tractor-trailers and pickups to avoid Border Patrol highway checkpoints that have long been the last line of defense for stopping all traffic headed farther into the United States.

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This is not oil. (Photo by West Midlands Police.)

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The traffickers are smart enough to masquerade their shipments as ones related to the roads’ intended use.

On a weekday morning in early March, 18,665 pounds of marijuana were caught being smuggled aboard two trucks, one a flatbed, the other a tanker truck driving through the Briscoe Ranch on a road that circumvents a Border Patrol checkpoint.

They were on a private road leased to energy companies and carrying what looked like supplies typically used in oil field operations but were instead loaded with marijuana. The two trucks yielded the most pot ever caught in one day by the Border Patrol’s Del Rio Sector.

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This will no doubt make conservative politicians reticent to approve further drilling in the region, while at the same time making certain elements of the left more sympathetic to the practice.