The safety issue alone is enough to stop them!
The safety issue is a red herring. Despite a ban on them dating from the 1980s, 800 Mexican trucks were allowed to continue operating in the United States. "A survey by the Arizona Republic newspaper found that those Mexican trucks allowed to operate in the U.S. have a superior safety record compared with U.S.-owned trucks," Daniel Griswold of the Cato Institute writes. The Transportation Department also found no safety problem with the trucks here under the new pilot program.