That was what I meant - putting it all down to gun ownership is a mistake, I think. A bit like saying "joy riding is just down to there being lots of cars about."

It's an important factor - without the guns you can't have the shooting, without the cars you can't have the joy-riders. But in principle it's possible to have societies with lots of guns and lots of cars which don't have those problems.

The crucial thing is where you have those things, together with people whose fantasy lives are filled with gun violence or car violence, and whose real lives are distorted in ways that means they are motivated to turn those fantasies into reality.

The only realistic way of tackling this, as Big Mick says, is to find ways of tackling the things that screw up young (and not so young) people in a society. Scews them up in such a way that, when the shit hits the fan, they turn to this kind of thing.

Making it a whole lot harder to get hold of the guns and the cars, and finding ways of changing the way modern media fills people up with violent images and fantasies would be fine as well, though complicated - particularly in the USA. I'm glad I live here instead.

But even if that could be done, it wouldn't tackle the basic problem. What is really dangerous isn't technology, it's people, when they get motivated to act in a destructive way - as is being so dramatcally demonstrated in the context of terrorism.