A long-term strategy to tackle the roots of violent crime is desperately needed – and I hope that’s what we’ll see next week from the Home Office’s serious violence strategy. But when we have children dying on the streets, the police’s first priority needs to be what can be done now to stop this waste of life.

That’s exactly what Metropolitan Police Commissioner Cressida Dick is doing. She’s taking sensible, practical steps that should bear results quickly.

The police response to rising violence must not just be swift but sure. While it is the murders in London which have horrified the public, the rises in violent crime, knife crime and gun crime are not restricted to the capital. Knife crime...