The murders of two 17-year-olds last weekend have catapulted knife crime back into news headlines. Jodie Chesney’s death stands out because she is the first girl out of 10 teenagers who have been killed by knives so far this year. While most victims of murders know their assailant, reports suggest Jodie was stabbed in the back by a stranger in a London park last Friday in a “random and unprovoked attack”. Last weekend’s other victim, Yousef Ghaleb Makki, was killed in an affluent Manchester suburb, and attended a private school. These two deaths show that knife violence involving teenagers is not, as is sometimes suggested, a problem confined to boys on tough estates. They remind us that there is no typical stabbing and thus no single solution.

The prime minister’s assertion on Monday that there was “no direct correlation” between rising crime and police cuts was hamfisted and disingenuous. After colleagues failed to back her up, and Metropolitan police chief Cressida Dick joined other senior officers in asserting that there is a link, the government backtracked. But the promise of a “series of cabinet-level ministerial meetings and engagements” promised by a Downing Street spokesperson on Tuesday rings hollow following months of inaction.

The homicide rate in England and Wales is at its highest for a decade; so is the number of teenagers killed with knives. Offences involving a knife or sharp instrument rose last year by 12%, while the number of those aged 16 and under treated for stab wounds by the NHS has nearly doubled in five years. The figures are shaming. The concern is that this week’s flurry of activity has more to do with the politics of news management than with policy-making.

A knife-carrying culture has taken hold in parts of the UK. This will take years of work to unravel, as the London mayor, Sadiq Khan, acknowledged when setting out plans for a new, public health approach in the capital. Pioneered in Chicago and also used in Glasgow, this method treats violence as a social contagion and employs multiple agencies to treat and root it out. Police numbers, contrary to Theresa May’s statement, are directly relevant. Officer numbers fell by more than 20,000 to 123,142 between 2010 and 2017. The comment by West Midlands police and crime commissioner David Jamieson that “the swagger is back” among criminals is unnerving. More funding is required because police work requires police. Evidence suggests that switching to a more holistic, “public health” style of enforcement twinned with prevention makes sense.

But to focus solely on policing is to miss the point spectacularly. Austerity’s impact on other services has been at least as damaging. Senior officers have said publicly that poverty and lack of opportunity are among the causes of serious youth violence. Young men and boys who believe the world offers them nothing become angry, afraid – and at risk of exploitation by criminal organisations that use them to sell drugs. Last year 32 out of 45 police forces reported an increase in violence they linked to the networks known as “county lines”. Children excluded from school are known to be at risk. For this reason, among others, the government must come down hard on the practice of removing hard-to-teach pupils, and incentivise schools to make strenuous efforts at inclusivity. Youth services must be scaled back up as a matter of urgency, and the provision of after-school activities for teenagers made statutory. When crime commissioners in the worst-hit areas describe a national emergency, hand-wringing will not do.