The global corporate tax reform that came into effect this year was something of a miracle. Less than a decade ago, few would have thought it realistic that most countries in the world would ever agree to close loopholes for corporate taxation, institute a global minimum rate, and decide how to apportion the new tax take — set to be more than $200bn a year — among themselves.

Yet here we are. Some parts of the global corporate tax reform are still to be ratified, but the minimum level is now being widely implemented. And if one miracle is possible, why not two? That is how we should look at recent stirrings of something similar: a multilateral effort to overhaul the flawed system for taxing super-rich individuals.

In February, the economist Gabriel Zucman — a scourge of wealthy tax optimisers everywhere — presented G20 finance ministers with a proposal for a global billionaire’s tax, at the request of Brazil. Brasília, which currently holds the group’s presidency, is keen to move to the next stage of the global tax agenda, which could be to close the loopholes that allow the world’s richest individuals to pay very little tax.