The resignation of Prime Minister Keir Starmer has once again plunged British politics into uncertainty. Britain is now poised to welcome its seventh prime minister in a decade: after David Cameron, Theresa May, Boris Johnson, Liz Truss, Rishi Sunak and now Starmer, yet another successor is waiting in the wings.For a country that often presents itself as a model of political stability and democratic governance, such an extraordinary turnover of leadership raises questions about the...