History tells us the reality: this spiral feeds itself. War breeds debt. Debt imposes austerity. Austerity feeds instability. And instability prepares the next war.

In 2022, war cut $1.6tn off global economic growth, the equivalent of a G20 country’s GDP evaporating. In 2023, another $1,000bn went up in smoke.

Europe, traumatised by Ukraine, is reviving its old reflexes. Germany has created a special fund of €100bn to rearm the Bundeswehr, unheard of since 1945. The target of 2% of GDP for defence, long ignored, has suddenly become sacred: 11 NATO member countries exceeded it in 2023. A record. States that struggled to fund their hospitals miraculously find billions for tanks and missiles.

But the hidden costs may be the heaviest of all.

Five years after lockdown, we are only just measuring its real impact on mental health and schooling. So what should we make of armed conflicts, or even of the impact they have on nearby countries, France included, on our peace of mind and our mental health? A bridge can be rebuilt in two years. But how do you rebuild the trust of a traumatised people? How do you decontaminate poisoned land? How do you break the vicious circle that leads from one war to the next?

The real bills of war are the ones you don’t see straight away. The ones that arrive years later, when the cameras have gone and the world has looked elsewhere. And nobody really knows who will pay those.

Because the reckonings we are shown are hopelessly partial. The history books record the number of dead. Sometimes the wounded, though we probably don’t grasp what a war wound really is. Then we (well, I) price Patriot missiles at $3.3M, but who accounts for the cost of a Syrian child who will never go to school? We put the reconstruction of Gaza at $53bn, but what price do we put on a traumatised generation? The $2,443bn of global military spending shows up in the statistics, but where are the 175Mt of CO₂ released by the war in Ukraine into our already suffocating atmosphere recorded?

So when will we have this full accounting? When will there be a great ledger recording, opposite every war profit, the irreparable losses it took to make it? Perhaps on that day, faced with the dizzying scale of the liabilities, we will finally understand that peace is priceless.

But nobody wants to open that ledger. There’s no money in it.