The most fundamental rule of politics
Elections are won by the party (or coalition of parties) which can attract the most support and agree a common programme. This applies whether you have a two-party state or a multi-party state. Sinn Fein have faced this in the Dail where they have been the equal-largest party, but Fianna Fáil and Fine Gael would rather set aside their historic differences and work together than form a coalition with Sinn Fein. In US politics, where the bell curve of left …