As much of the nation sweltered through the first major heat wave of 2011, the war of words in Washington was heating up as well. But while the temperatures will eventually subside, the tensions between rail and trucking interests seem unlikely to ease anytime soon.

What makes the latest flare-up noteworthy isn't so much the source of the controversy—recent proposals to raise truck weight limits—but the level of hostility generated. Not since former Roadway Express president Joe Clapp hit the speakers' circuit in the early 1990s has the rhetoric reached the pitch it did in May. Clapp, as you may remember, became a fixture at trade shows, conferences, and even congressional hearings, where he spoke out against a rail-backed media campaign that used graphic photos of truck-car accidents to illustrate the alleged dangers of allowing bigger double and triple trailers on U.S. highways.

Fast forward to May 2011, when the American Trucking Associations (ATA) issued comments that were more than vaguely reminiscent of remarks made by Clapp two decades ago. In a statement responding to "fallacious claims about the trucking industry," ATA president Bill Graves launched a full-frontal assault on rail interests.

"For years we've seen a number of organizations proselytize about the dangers posed by the trucking industry," he said. "These groups have for too long co-opted the legitimate grief of Americans who have tragically lost family members on our nation's highways in order to advance an agenda designed to hurt our economy and our industry and benefit trucking's competitors and well-heeled union interests. Issues as important as highway safety demand that legitimate stakeholders be honest and upfront with the public and deal with facts and science.

"The fact is, the trucking industry has never been safer and the continued improvement is due in part to the hours-of-service rule these groups have attempted to litigate and blackmail out of existence.

"These same concerned citizens claim to speak for many Americans on the issue of truck productivity, but it seems pretty clear they speak for the railroad industry, which lines its pockets at the expense of shippers and consumers they hold hostage."

Although he didn't mention it by name, the target of Graves' remarks was the Coalition Against Bigger Trucks (CABT), a special interest group that is fighting attempts to raise truck weight limits to 97,000 pounds from the current 80,000. Two weeks earlier, CABT, which is supported by the rail industry, had released a study showing that nearly three-quarters of Americans "overwhelmingly and consistently oppose allowing bigger, heavier trucks on American highways." Among the reasons cited for their opposition was "the increased threat of accidents posed by heavier trucks."

The integrity of that study—and indeed the credibility of the group itself—has since been questioned by the Coalition for Transportation Productivity (CTP), according to the ATA's newspaper, Transport Topics. (The CTP, a group supported by the trucking industry, has been lobbying for the use of heavier trucks.) According to the newspaper, both the CABT and the company that conducted the study declined to discuss the research methodology.

Granted, there's nothing new about using safety concerns to advance a political agenda. The trucking industry itself has exploited safety issues—like the hazards posed by street-level railroad grade crossings—in its own advocacy efforts. But a suspect study like CABT's does nothing to advance the argument; it merely exploits public fears to advance its position.

It has been long established that there's a place for both trucks and rails when it comes to moving the nation's freight. It would be best to let the market determine how that freight will be allocated between the two modes. And we would all be better served if both sides accepted the fact that a peaceful coexistence is in everyone's best interests.