Living in London, I'm taking an active interest in the riots.
No-one I've read yet seems to have grasped that this is the new normal. We had a stable situation at a certain level of criminal activity. The criminals have suddenly understood that with a level of organisation, they have capabilities completely beyond the police to handle. It doesn't help that they may well have better comms than the police. Situations like the student protests and the Bristol riots showed categorically that the policing system bequeathed to the new government simply cannot handle almost any disorder. That is allied to an officer cadre with little to no public disorder experience other than kettling football fans.
The situation will require dramatic increases in police capability. Maybe martial law, maybe citizen militia, maybe doubling the size of the Met, but certainly new equipment like water cannons. Currently, the Metropolitan police are failing to handle the situation despite drawing on almost all the free policing resources in the South-East. Those resources will be increasingly spent as effective forces as exhaustion hits them. If the riots continue to next Monday (as I anticipate), the police resources will simply deteriorate.
But what has happened in London can happen in ANY significant city in the UK. Unarmed police with nothing more than a stick and shield are not effective against mobile and diffuse mobs. No doubt people will talk about "things returning to normal". Fools.
This IS the New Normal until police resources are significantly increased. And the level of re-organisation required is going to take months and years to put into place.