As successive heatwaves hit Europe, air-conditioning (AC) has emerged as a new front in the international “culture war” over climate action. France, Germany and the UK have experienced record-breaking heat and thousands of heat-related deaths this summer, with June temperatures in many regions passing 40C. This has drawn attention to the relatively low rates of AC use in these countries – and in Europe as a whole – especially when compared to its widespread adoption in the US.