The first rule of forecasting, the financial journalist Jane Bryant Quinn once observed, is this - give them a forecast or give them a date, just never give them both.

So, here’s a not very bold forecast. Generative artificial-intelligence models like ChatGPT will revolutionise the economy. We just can’t say when.

Nor can we say where. Among the key questions lost amid the flurry of commentary on generative AI is which countries will benefit, and which will not.

Will the United States, a first mover in this domain, grow even more dominant economically? Will developing countries’...