Leading article: The special interests take off

The special pleading was predictable enough. Emboldened, perhaps, by recent success in his other chairmanship (at Liverpool FC), Martin Broughton of British Airways has inveighed against the "completely redundant" security restrictions he feels have been imposed on British airports. Airline lobbyists, including the Heathrow owner BAA, rushed to endorse his words yesterday.

The targets of Mr Broughton's ire range from a requirement that passengers' shoes be removed for inspection (a consequence of the "shoe bomber" Richard Reid) to the stipulation that laptops be separated from bags for scanning. Mr Broughton hopes to position himself on the side of the put-upon regular traveller. But the airline lobbyists have a commercial interest here. The likes of BAA want passengers spending money in their shopping malls, not clogged up in security zones. So their protests should be taken with a substantial pinch of salt. As for the howls from Michael O'Leary, the chief executive of Ryanair whose suggestions for easing airport security are much more radical, the less attention paid to him the better.

These measures are there for a reason. Modern terrorists are obsessed with international aviation, seeing it as a rewarding target for their destructive ends. The foiled plans of Reid and the would-be Detroit bomber Umar Farouk Abdulmutallab are testament to that.

Yet there is a danger of overkill. And Mr Broughton is justified in complaining that different security measures seem to be enforced in different countries.

Ultimately, the cost in liberty and inconvenience caused by rigorous security checks has to be weighed against the benefit of foiled attacks. Because the former is tangible and the latter is potential, it is a difficult calculation to make; but it is the duty of the Government to attempt it nevertheless. And there is indeed a case for a fresh inquiry into existing airport security arrangements.

The success of terrorism can be measured by the reaction of its target. In matters of airport security, the response needs to be determined by evidence and risk, rather than the commercial interest of airlines.