Last autumn, London hosted two large demonstrations against government spending cuts. First were the firefighters, and nobody but the firefighters themselves remember it. Had they, like the student demonstration for free education, gone and totalled Conservative Party headquarters then, as with the students, public support would be strongly behind them.

Nobody is saying that activists should be as destructive as possible to all property in sight. But as part of a movement that has tremendous moral force and faces targets who care more for property than for people, property damage has a proven track record of effectiveness in bringing about justice that would otherwise be denied. Conversely, the history of just politely asking for change echoes loudly with the yawns of the ignored.