Here comes April, and with it the blossomed pear-tree and the chaffinch on the orchard bough – or so Robert Browning would have us believe. In my Sixth Form college, spring is announced rather differently: heralded not by birdsong but by the now-annual Lockdown Training Session, a grim modern-day equivalent of ‘Duck and Cover’ in which staff and students rehearse what to do when a deranged gunman comes knocking.

The session, delivered simultaneously by subject teachers during period two on a scintillatingly bright Tuesday morning, begins with a tannoy announcement from the Principal. Adopting the calm voice of an aircraft pilot whose plane has hit unexpected turbulence, he reassures students that what follows is a wholly preventative measure and that the need for actual lockdown is vanishingly small. Students’ faces are fixed with wry smiles in a show of performative nonchalance, yet their steely eyes betray an attentiveness I can only dream of in my ordinary lessons. Suddenly, I’m transported back to my own youth in the 1980s, where the threat of nuclear annihilation provided a humming backdrop to video rental stores, Sony Walkmans and New Romanticism.

Next comes the 30-second blast of the Lockdown Siren: a bleating screech punctuated by a relentless “Lockdown! Lockdown!” that gets teeth grating. It’s equal parts Jon Pertwee-era Doctor Who and some forgotten public information film from the 1970s — theatrical, absurd and quietly chilling. All smiles vanish.

It’s now my turn to deliver a PowerPoint which outlines the procedures for ‘Invacuation’, a clumsy neologism fit for a jarring new age. My advice to lock doors, eliminate sightlines and maintain silence surely needs a Jack Reacher-esque authority rather than the reedy voice of a teacher more accustomed to reading sonnets aloud.

The macabre digestif to this unsettling fare is a short video in which a series of alpha personalities – Rugby player James Haskell, Taekwondo champion Jade Jones and survivalist Bear Grylls – each crow about their heroic feats before solemnly declaring that even they would “Run – Hide – Tell”. If a 19-stone rugby flanker is shitting himself, what chance have 17 year-olds and a 140 pound declaimer of poetry, I sardonically wonder.

In many ways, it’s the very orderliness and measured calm of the ritual that is most disconcerting, especially when an underlying sense of dread permeates the lives of all of us, but especially our youth. Consider a typical 17 year-old: at 12 they were told they were in danger of dying from an invisible virus; at 14 they absorbed the sudden drumbeat of ‘The Russians are coming!’ accompanied by nuclear sabre-rattling; and now, at 17 they are witnessing the latest, bloodiest incarnation of the Israel-Hamas conflict, with its horrifying body counts scrolling 24/7 on the news. Add to this the constant siren wail of ‘climate catastrophe’ and I can’t help but feel sorry for the poor sods.

And here we are, the banal competence of rehearsing the worst-case scenario, as if ticking off another item on the risk-assessment spreadsheet while outside the window the pear tree is doing its indifferent spring thing.

As the class now settles back into its writing activity, I consider how the changed fabric of the college building itself reflects our increasingly risk-averse society. Battalions of bollards form metallic crescents around the main entrances. Familiarity has made them nearly invisible, yet each time my eye catches them a small chime of deep unease still sounds. Once, such fortifications would have signalled a society under explicit siege – hostile armies or terrorist campaigns visibly at the gates. Now they are simply ‘best practice’: quiet insurance against the vehicle-as-weapon, the lone actor, the unpredictable. The college has grown a carapace, and we barely notice we’ve put it on.

Read More: School Lockdown Drills Are Keeping Britain’s Children in Perpetual Terror