There is a black and white photograph that’s routinely published when the subject of Scotland’s thorny and inglorious relationship with knife crime is written about.

Snatched by a news photographer in 1971, it captures a fleeting moment when a plain clothes detective in the centre of Glasgow fends off an open razor-wielding thug, while simultaneously reaching inside his raincoat to retrieve, what we can only assume to be, his own weapon.

That the moustachioed cop manages to retain an untipped cigarette clenched between his lips during the exchange illustrates sublimely the workaday nonchalance with which knife violence is enacted in these parts.

The phrase “stab you as soon as look at you” is often used to describe a particular kind of person, and as a warning to avoid the sort of environs they inhabit.

Many people still believe Glasgow, in particular, to be the caricature it acquired in the 1920s and 30s when working class razor gangs like the Bridgeton Billy Boys and the Norman Conks routinely turned the streets into blood baths.

Scotland’s relationship with knife crime has once again been thrust into the spotlight following the deaths of two teenage boys earlier this year – Amen Teklay, 15, and Kayden Moy, 16 – both allegedly stabbed to death in separate incidents.

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Tomorrow John Swinney will host a knife crime summit, where he will gather together justice and education secretaries, ministers for children and for victims and community safety, cross-party MSPs, as well as youth workers and representatives of community programmes.

The first minister is seeking answers to questions about what motivates young people to carry knives, what........

© Herald Scotland