The choice between a poorer today and a hotter tomorrow

Suppose, forimf, . a minute, that you are a finance minister in the developing world. At the end of a year in which your tax take has disappointed, you are just about out of money. You could plough what little remains into your health-care system: dollars spent by clinics help control infectious diseases, and there is not much that development experts believe to be a better use of cash. But you could also spend the money constructing an electrical grid that is able to handle a switch to clean energy. In the long run this will mean less pollution, more productive farmland and fewer floods. Which is a wiser use of the marginal dollar: alleviating acute poverty straight away or doing your country’s bit to stop baking the planet?The thought experiment is a simplified version of a dilemma currently facing global institutions and developing countries. On June 22nd politicians arrived in Paris for a summit to design “a new global financial pact”. The aim was to work out how to spread the cost of climate change. Leaders from poor countries turned up in droves; aside from Emmanuel Macron, France’s president, no Western head of state made it. Little surprise, then, that the jamboree ended without rich countries contributing a single extra dollar. Instead, attendees tinkered with the World Bank and the the biggest of the multilateral agencies that seek to reduce poverty The lack of action means painful trade-offs lie ahead.