The real problem begins when debt grows consistently faster than national wealth and financing it becomes increasingly costly.
This is because borrowing is no longer as cheap as it was a few years ago. Interest payments are rising sharply. A Senate committee estimated in June that the cost of public debt could exceed 77 billion euros in 2026 – an increase of nearly 12 billion in a single year. According to the same estimate, this would represent around 2.5 percentage points of GDP.
And this money has one distinctive feature: it does not build a school, fund a hospital, or pay a teacher, a police officer or a researcher. It simply pays off the debt accumulated previously. The more this burden increases, the less room for manoeuvre governments have to fund other things without increasing revenue, cutting other expenditure or borrowing even more.
This marks the start of the most problematic cycle: borrowing to finance deficits, then devoting an increasing share of the budget to paying interest on the money already borrowed.
France is obviously not yet in the extreme scenario of a country unable to find lenders. It continues to borrow on the markets and has a substantial economy. But the trajectory warrants frank scrutiny. As recently as June, the Banque de France estimated that, without sufficient additional savings, the debt-to-GDP ratio would continue to rise in the coming years and could reach 122 per cent of GDP by 2028.
The issue goes far beyond the usual clash between those who want to ‘cut spending’ and those who want to ‘raise taxes’. Behind these slogans lies a far more complicated equation: how to finance pensions, healthcare, education, defence, the energy transition and public services in an economy where growth remains weak, whilst preventing debt from rising indefinitely?
Each political camp offers different answers to this question. Cutting certain expenditure, raising certain taxes, tackling tax loopholes, reforming the state, promoting growth, and pursuing industrial policy: the choices are deeply political. But the maths itself has no opinion.
And today, it tells us something quite simple.
3,536 billion euros.
France’s record level of public debt has now been reached.
And unlike many records, no one should really want to break the next one.
