Peel through the numerous layers of border security programs enacted since 9/11 and you will discover that the Customs-Trade Partnership Against Terrorism (C-TPAT) program, although rarely receiving much media attention, is the true backbone of the partnership among U.S. Customs, carriers and other supply chain partners.

Recent memos from the U.S. Customs and Border Protection (CBP) suggest this backbone is about to get a lot stiffer and carriers will likely feel much of the impact from this change in direction.

So far participation in the program has been voluntary in a way. I say that because participation in C-TPAT was also made a prerequisite for participation in the expedited release program Free and Secure Trade (FAST). So for mid-sized and large Canadian carriers, who depend on transborder hauls for nearly half their income, there really was no choice but to join C-TPAT and hundreds did so. As one trade attorney suggested, C-TPAT was the most "non-voluntary voluntary program" that U.S. Customs had ever devised.

But at least the regulatory yoke of C-TPAT was not a particularly heavy one.

To participate in C-TPAT, carriers complete a security questionnaire and agree to develop programs to enhance internal controls throughout their supply chain. And so far U.S. Customs, provided it found those plans to be satisfactory, has allowed each supply chain partner to tailor its security program to its own business needs. There was no attempt to adopt a one-size-fits-all security regime.

That may be changing.

Anyone willing to take an unbiased look at the security of the continent’s supply chain three-and-half years after Sept. 11, 2001 would have to admit that it remains vulnerable to terrorist attack, despite the progress that has been made. Homeland Security Secretary Tom Ridge said as much when he announced his resignation late last year.

So it’s no surprise that the Department of Homeland Security (DHS) and U.S. Customs are feeling the heat from the U.S. Congress to increase the level of physical inspections and other security measures. Nor should it be forgotten that C-TPAT was designed with the understanding that its benchmarks would be raised over time. As C. Stewart Verdery, assistant secretary for policy and planning within DHS’s Border and Transportation Security Directorate, recently told the U.S. media: "This is not a program that can sit still. It is something that is going to change over time."

What all this is boiling down to is a fundamental debate about whether C-TPAT should remain a voluntary partnership with industry or a regulated program.

The two "informal" drafts of proposed changes to C-TPAT released by U.S. Customs late last year have left carriers and shippers wary about just how much of C-TPAT will be voluntary. While C-TPAT director Robert Perez stressed that the intention is to only tighten certain rules for participating in the program, such as the requirement of tamper-evident bolt seals on container doors, supply chain stakeholders who have seen the drafts say C-TPAT will no longer be a set of guidelines. Renee Stein, senior manager for worldwide trade and customs compliance for Microsoft, told the media that terms like "should" and "recommend", which permeate the C-TPAT agreement, have been replaced by the word "shall" in the drafts.

If that’s the route that U.S. Customs intends to go, I’m not opposed to it. C-TPAT would benefit from more clarity on what is considered a requirement versus what is asked of carriers and supply chain partners as a best practice. Stricter standards may also help prevent another terrorist attack, after which the greatest danger to the continent’s economy would come, as suggested by long-time Washington lobbyist Carl Bentzel, not from al-Qaida but from an enraged American public that would force the U.S. government into far more draconian security measures.

But I must also ask, where’s the beef?

When will C-TPAT-approved carriers and shippers finally get that elusive "green lane" for secure cargo that has been promised? (Getting through a designated FAST lane in a few seconds is no perk if your trucks have to wait hours in congested border traffic to get there). How about a government policy that ensures that in the event of another terrorist attack that C-TPAT participants will be guaranteed border access within a certain matter of days?

When "should" becomes "shall", guidelines turn into standards and the government must reconsider the benefits of compliance if it still expects a true partnership with the transportation community in the fight against terror.