Security checkpoints create points of insecurity

Like any evolving system, predators adapt to exploit the very defenses their prey have developed.

Long queues for security and check-in made an "excellent target" for potential bombers, the Tory transport spokesman told MPs.

Julian Brazier, a former SAS soldier, said that jihadists might adopt similar techniques as those seen in Iraq, where civilians were often targeted at checkpoints.

"A bomber can simply walk into a terminal carrying or wheeling a large bomb in a suitcase," he said. "The plain fact is that long, densely packed queues represent a hugely tempting target to terrorists."

This amplifies the point I made in an earlier UFTS post. One successful bombing of a queue or crowd will make the entire system vulnerable to spoof bombs and empty bomb threats: authorities will have to clear the facilities under threat, regardless of how many threats prove hollow. The effect of one bomb will be multiplied many-fold and cripple Western economies.