Why America’s political parties are so bad at winning elections

Every four years the American presidential primaries roll around to remind Americans how weak, clumsy and negative their major political parties have become. The news media’s red-and-blue maps, the repetitive partisan standoffs in Congress and the drama created by the polarisation of the parties create the impression that they hold tremendous sway, that Americans are devoted to either the Democrats or Republicans and obsessed with their prospects. The reality is more muddled and dispiriting.