WASHINGTON -- When it comes to possible border skirmishes between the U.S. and our neighbor to the south, there's illegal drugs, immigration reform and a turf war over who should travel on our roadways.

Under the North American Free Trade Agreement, or NAFTA, our highways are supposed to be open to Mexican trucks. However, last month, Congress put on the brakes by cutting off funding for a cross-border trucking program. Now, Mexico is retaliating by slapping tariffs on $2 billion worth of U.S. goods, making them more expensive for Mexican shoppers, and perhaps for us, as well.

Martin Rojas of the American Trucking Association said that trade hikes could be passed onto American shoppers.

"Any time you have increased transactional cost, those costs are going to end up impacting the final cost of the product that's for sale," said Rojas.

A group of independent truckers -- opposed to Mexican cross-border trucking -- says it's no big surprise that big trucking companies want the borders open.

"Certainly some larger trucking companies in the U.S. would like to have access to that labor pool," said Rod Nofziger of the owner-operator Independent Drivers Association, "a cheaper labor pool."

Besides the debate over the bottom line, there's also concerns that Mexican trucks simply aren't safe.

"The Mexican government has no control over their transportation system," said Bret Caldwell of the Brotherhood of Teamsters. "They have no computer databases. They have no drug testing facilities. They have no wage and hour laws."