US counter-terrorist measures siezed the headlines as the year began, with sky marshalls, fighter escorts and a host of new checks for travellers. The real challenge, however, is to translate this unilateral effort into an effective global response.

Terrorists do have something in common with airlines after all: they both operate internationally. The comment came from British Airways chief executive Rod Eddington speaking in Washington at the end of an extraordinary few weeks of security alerts on the North Atlantic. His point is not simply to highlight a certain irony, but to stress that security is an international concern and should be determined internationally. It is hard to disagree with such a sentiment, but even harder to put it into practice as the USA is finding out. Indeed, the issue is threatening to drive a wedge between the USA and its aviation trading partners.

The alarms began to sound as early as Christmas Eve when Air France pulled six flights to Los Angeles following US security fears. By New Year's Eve, flight BA223 found itself being escorted into Washington by US Air Force F-16 fighter jets - presumably ready to shoot it down in the event of a hijacking. The same flight was cancelled a couple more times and aviation security stepped up across the nation, not least for inbound passengers. A new visa programme is underway.

It appears that the initial scare over BA223 may have been caused by inconsistencies in transmitting information about passengers on board to the many US authorities that now demand it. The extent of the data that would be sent from European carriers itself had threatened to create a transatlantic rift late last year. Eventually the US Department of Homeland Security reached a compromise with the European Commission in December.

But no sooner had that fence been repaired than the same US Homeland Security officials declared on 29 December that foreign-flag carriers flying using US airspace would have to carry armed sky marshalls, or at least where the agency deems the flight to be a security risk.

Such measures look very different depending upon where you are standing. From a US perspective they clearly represent no more than swift, decisive action against the very real threat of terrorism. Clearly it sent a loud message to would-be terrorists everywhere that the US was armed and ready.

Robert Poole of the US market-oriented Reason Public Policy Institute says that nations have been setting conditions for airworthiness of flights to and from their territory for a very long time. How is setting requirements for adequate security any different? But he adds: "It is unfortunate that the Bush administration isn't more sensitive to the prerogatives and concerns of other governments, nearly all of whom are supposedly allies in the struggle against terrorism. These challenges would be somewhat easier to deal with if everyone were working together more collegially." They would also be easier to deal with if the dispute did not centre, literally, on a loaded gun.

To those outside the USA the recent actions do indeed look suspiciously like unilateral decisions taken behind closed doors in Washington and imposed on the rest of the world. "In the past, no country has ever tried to impose on other countries any measures of aviation security," points out Rafi Ron, who as the former security director for the Israeli airport authority has more experience of terrorist threats than most.

By the middle of January, Homeland Security had made its point and was prepared to consider a rethink, dispatching its number-three official to Brussels to talk about the sky marshall requirement. He relieved many by toning down the US stance and rhetoric, and assured Europe that the requirement for armed guards would likely not be applied to nations that develop a comprehensive system for vetting passengers and crews.

In short, another transatlantic compromise looked like being safely reached. But that still leaves the unsettling question of whether it is a desirable or, more importantly, an effective way to develop a new global security framework. Seeing it evolve unintentionally through a series of ad hoc compromises hardly seems a substitute for joined up international thinking.

In any case, while sky marshalls and fighter escorts may make headlines, the real solution lies in preventing terrorist threats from making their way into the air transport system in the first place. Once they are there it is too late to legislate against a catastrophe - sky marshalls or not. Ensuring that terrorists do not get into airports or aboard aircraft is a global responsibility and will require an unprecedented level of cross-border co-operation and a grinding degree of detail. There are no shortcuts.

Whether the existing international bodies are up to the job of orchestrating the effort to deal with the threat of the new terrorism remains to be seen. And until then the USA is perfectly entitled to sieze the initiative, but more effectively if it brings the rest of the world along too.

Source: Airline Business