Introduction: When Donald Trump pulled the United States out of the Paris climate deal, the world reacted with outrage. And rightly so: the agreement represents a remarkable achievement in international diplomacy – a breakthrough after 20 years of failed climate negotiations. But as we rally to defend the Paris deal against the onslaught of an ill-informed bully, we need to resist the temptation to cast the agreement as some kind of saviour. It is not. Its purpose is right and noble, but its substance is nothing short of dangerous.