Rishi Sunak, with almost daily input from Sir Jeffrey Donaldson, the Democratic Unionist Party leader, has just delivered a deal on the Windsor Framework that is notably pro-Unionist. He has managed to do so in the face of EU intransigence, an unhelpful White House, the ‘resistible rise’ of Sinn Fein in the Republic of Ireland, hard-line Loyalist rejectionism, and purist Brexiteer scepticism.