It seems several lifetimes ago that US officials were worrying about fronting up to Vladimir Putin, placing sanctions on foreign leaders to punish them for killing their own people and welcoming huddled masses of refugees into the country. In fact, as it turns out, this sort of crazy stuff was happening just four years ago! And if you don’t believe it, read Samantha Power’s memoir, The Education of an Idealist. It is sobering to reflect how quickly the world has moved on. Equally, Power’s book unintentionally provides several clues as to why this might have happened.

Power was, as the title suggests, an idealist in politics. She was the quintessential Obama groupie, working in both his administrations, latterly as the US representative at the UN, a thankless task at the best of times. Before serving she established a reputation as a scholar of foreign affairs,