Trouser-bomb clown attacks - how much should we laugh?

OMG - why aren't we all already dead?

Even if a security miracle occurs and the option of sneaking a bomb onto planes is somehow removed, there still exists the option of shooting planes down. Shoulder-launched homing missiles can be had in some parts of the world. From those same parts of the world, huge tides of illegal immigrants and drugs routinely move into Western nations despite all our governments' efforts to stop them. It would not be hard to move small packages like "double-digit" (SA-14, -16, maybe even -18 if available) anti-aircraft missiles along the same routes.

So, assuming a well-funded, numerous, committed, competent terrorist enemy without scruples and with a broad base of support from which to draw numerous recruits, airliner attacks can't practically be prevented. Planes should be exploding every day, really: if not planes then trains, another situation where blast effects can be magnified. If neither should suit, a few men with automatic weapons can bring a city grinding to a halt fairly easily, as the residents of Mumbai will tell you.

But the truth of the matter is that there is no such enemy out there. Funds are occasionally available, true; the 9/11 plotters were quite well-backed, and even if a terrorist group has no access to oil or gas revenues there may be the option of dealing in heroin as the Taliban do. (Note that all of these sources of money ultimately come from us.)

But people who are willing to kill innocents en masse as a primary goal are fairly rare birds. In Afghanistan you can easily hire large numbers of men for quite small sums of money to do fantastically dangerous things like taking on the British and American armed forces in open combat; some will even cover their own expenses, and a fair few will happily mount a suicide strike against Western troops. In general, just like the Western troops themselves in many instances, these fighting men are quite willing to accept a lot of collateral damage to local people as a cost of doing their main business.

But an awful lot of them would no more intentionally blow up an airliner, nightclub or train full of peaceful folk, would no more open fire into a crowd of unarmed civilians, than a Western soldier would. The likelihood of such squeamishness goes up markedly when you're recruiting outside the unruly and often aggrieved warrior tribesmen of central Asia, as you'll probably have to do for operations against the West.

Assembling a team of committed, loyal mass-murderers is actually very difficult, then, as such people are rare and hard to find. In fact, as we've pointed out in these pages before, the average size of potential terror cells operating in the UK and known to MI5 is ten members. This strongly suggests that five people or so is the upper safe limit before there's a strong chance of a cell having an informer in its midst or among its acquaintance.

It's just about possible then that one might assemble a loyal team of five or a few more and manage to remain, if not off the security services' radar altogether - it normally turns out that successful terrorists were on file somewhere - then far enough down their list to give you some time before you get put under surveillance.