What do presidents Clinton, Bush, and Obama have in common? Probably several things, but after President Obama’s recent trip to Guadalajara, one thing is certain. None of them has shown much interest in abiding by the North American Free Trade Agreement (NAFTA), particularly when it concerns our third-largest trading partner, Mexico.

Signed into law in 1993, NAFTA was supposed to eliminate barriers to trade among the United States, Canada, and Mexico. Under terms of the deal, the United States agreed to give both Canadian and Mexican truckers full and free access to U.S. highways. But nearly 16 years later, Mexican truckers remain stuck in idle, barred from traveling beyond U.S. commercial zones that extend roughly 25 miles along the border.

Under the original schedule, NAFTA would have opened U.S. roadways to both Canadian and Mexican truckers on Jan. 1, 2000. In 1995, however, the Clinton administration put the trucking provisions of NAFTA on hold – but only for Mexican truckers – citing safety concerns. (Canadian truckers, meanwhile, got the green light to move freely about the country.)

Things didn’t progress much further during George W. Bush’s tenure in office. In 2001, Congress enacted legislation mandating that various U.S. government agencies meet 22 safety requirements before Mexican truckers would be allowed to travel beyond commercial zones. In 2002, Transportation Secretary Norman Mineta confirmed that the requirements had been met, but legal challenges kept the program tied up until 2004, when the U.S. Supreme Court ruled in favor of the Mexican truckers.

Finally, in February 2007, the Department of Transportation announced a one-year pilot program that would allow selected Mexican carriers to make deliveries beyond the U.S. commercial zones. To participate, truckers had to pass a U.S. safety audit, including a complete review of vehicle inspection records, driver records, and drug and alcohol testing results. Despite protests by the Teamsters, the Owner-Operator Independent Drivers Association, Public Citizen, and the Sierra Club (which challenged the program on various safety, security, and environmental grounds), it appeared that we had finally reached resolution.

But it was not to be! Barely two years into the pilot, President Obama effectively brought the experiment to a halt in March 2009 when he signed a spending bill that ended funding for the program.

This time, however, Mexico fired back, slapping tariffs on over $2.4 billion worth of U.S. imports. The affected items range from produce like grapes, pears, cherries, potatoes and onions to toothpaste, curtain rods, and sunglasses. In June, a Mexican trucking group, Canacar, filed a $6 billion claim against the U.S. government for its failure to comply with NAFTA.

Transportation Secretary Ray LaHood has been charged with developing a plan to address lingering safety concerns and ease restrictions on Mexican truckers, but so far, nothing has been presented. Many thought that President Obama and Mexican President Felipe Calderón might resolve the issue during an August meeting in Guadalajara, but to date, nothing concrete has emerged.

There is more at stake here than $2.4 billion in tariffs. The United States relies heavily on trade with its NAFTA partners. In 2008, imports and exports between the United States and Canada totaled $601 billion, and U.S.-Mexico trade amounted to $367 billion.

Certainly, safety should be our foremost consideration, but the DOT adequately addressed that when establishing the pilot program’s parameters. Let’s not create safety, environmental, or immigration straw men simply to satisfy the Teamsters, the Sierra Club, or any other special interest group.

Let’s suck it up and do what we agreed to do nearly 16 years ago: treat both our NAFTA partners – Mexico and Canada – equally. There are enough countries mad at us. Let’s not add another.