How many times does this need to actually happen though before the senior people in charge of the security are fired and new people brought in, because it is obvious time after time they are not able to do the job properly.But what more does Andrew want the authorities to do?
We already have endless queues for members of the public who want to get in to see an MP, a glass barrier separating the Commons chamber from the public gallery and armed police officers on every street corner.
I would rather see the occasional incident like this than put up with even more intrusive security precautions.
You may say that it could have been more serious. But I am reminded of the environmental activists who bought platform tickets at a suburban station and then pointed a cardboard tube at a train of nuclear waste as it trundled past on its way through London en route from Dungeness to Sellafield.
The activists then announced that it could have been a rocket launcher, which showed that it was much too dangerous for these trains to be allowed to run through residential areas.
They were not taken seriously and I am not sure we should worry about today's Greenpeace demonstrators either.