As the third anniversary of July 7th approaches, new security measures aimed at preventing another terrorist attack have been unveiled by the Department for Transport and British Transport Police.
Airport-style x-ray machines (complete with saturnine operators) are to be introduced at certain Tube and mainline rail stations from this week. The machines will be used to scan passengers bags, and come on the heels of those knife scanners that stop people boarding with a switchblade tucked up their sleeve.
Additionally, sniffer dogs, trained to catch the merest whiff of explosive substance, will be introduced to pad around key stations.
However, following trial runs in 2006 and over the past six months, the decision was made to refrain from introducing these measures at every station, for fear of the delays they would cause to a system not particularly well known for providing smooth, trouble-free journeys.
Two questions: will it work, and what effect will it have on passengers? With the limited deployment of the pups and machines at a "handful" of stations, we assume they'll be rotated, lest Terry Terrorist gets wind of the location and simply gets on at a different stop. It's no foolproof method, and is arguably nothing more than a salve to passenger concerns - but with a system as open to attack as the Tube, it may be the best we can hope for.
As for the impact on commuters: according to the BTP's Supt. Phil Trendall, the measures will "not result in train delays", though we'll believe that when we've actually seen it in action. As transport minister Tom Harris perspicaciously noted: the public are unlikely to accept any major delays.