Cocaine Highways: Post-NAFTA, Most Drugs Cross U.S. Borders in Trucks

April 16, 2009— -- Most of the drug shipments smuggled into the United States by the Mexican cartels are hidden in trucks that drive across U.S. border checkpoints in plain sight, with little fear of inspection, U.S. law enforcement officials tell ABC News.

Only about 5 percent of trucks coming into the country from Mexico are inspected, according to U.S. officials.

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"It is just too costly and too slow given the volume of trucks to actually try to stop and inspect each and every truck," said Juan Zarate who dealt with the issue in the Geroge W. Bush White House as Deputy National Security Director.

The number of trucks coming into the U.S. has steadily increased since the passage of NAFTA in 1993. Almost 3,000,000 loaded container trailers crossed at border checkpoints last year.

"It does open up the potential for drug networks to take advantage, but I think it is something we have to find alternative ways of addressing," said Zarate.

Any attempt to inspect all trucks crossing the border, "would have a hugely negative impact in terms of commercial traffic and trade between the United States and Mexico," said Zarate, who also held the position of Deputy National Security Advisor for Combating Terrorism.

"You would see lines like you wouldn't believe," he said.

The Mexican cartels' fleet of 18-wheelers has long since replaced the Caribbean air drops and speed boats used by the Colombian cartels in the 1980's and 1990's, the era of "Miami Vice".

And major cities at interstate highway junctions, like Atlanta, have become important hubs for the Mexican cartels.

"Atlanta is a central trans-shipment point for pushing narcotics to some of the largest distribution cells in the United States," said Rodney Benson, the Special Agent in Charge of the DEA office in Atlanta.