Three episodes and five arrests later, what picture of ‘terror’ is beginning to form in Britain this time? And would a new prime minister and home secretary make this picture any different? Gordon Brown has repeatedly invoked the “British way of life”, which is not to be “undermined”. Jacqui Smith, his new home secretary, has added her own emphasis on the balance between “vigilance and good humour”. The good humour was amply evident after the far more lethal 7/7 bombings in London. However, the Glasgow attack puts Scotland — free, so far, from Irish or Islamist fears (Lockerbie being the only exception) — on the map of terror. For the police and the home office, balancing security, intelligence, surveillance and the prevention of an anti-Muslim backlash is the immediate challenge. Post facto security measures in and around airports and nightclubs are, in any case, token gestures that are, in actual terms, far less important than sustained surveillance and interpretation of intelligence. This has become almost unmanageably complex in Britain. MI5’s outgoing chief said late last year that the security service was monitoring 1,600 individuals in Britain, of varying degrees of suspiciousness, in 200 groupings involved in 30 distinct, and presumably thickening, plots. Hence the latest episode has elicited a “critical”, rather than just a “severe”, alert.

In international terrorism today, everything seems to be connected to everything else, through organization or inspiration. So the profile that has begun to emerge, rather quickly in this case, is an al-Qaida-inspired set of three, forensically-connected attempts, which, although amateurish, are reminiscent of Iraqi car-bomb episodes involving petrol, cylinders and nails. But none of those arrested so far is a British national, most of them being rapidly radicalized west Asians who have come into England and Scotland recently, apparently looking for work. “These are not your young people,” the police have assured Muslims in Glasgow. But the clues all point to an organized group or “cell” rather than isolated figures. It is wise of Mr Brown not to use this situation to make a political point at his predecessor about Iraq, but to talk of long-term threats in terms that go beyond the purely legislative. But tougher vigilance and surveillance are likely to become part of the “British way of life”.