Angry unionism is nothing new. It was born in anger in the 1880s – when it recognised the threat posed to it by the Home Rule crisis – and it has remained angry ever since. Angry in 1972, when the Stormont parliament was closed. Angry in 1974, when power-sharing arrived. Angry in 1985, when the Anglo-Irish Agreement was foisted upon it. Angry in 1993, when the Downing Street Declaration stated the British government had no “selfish strategic or economic interest in Northern Ireland”. Angry right now, because the Northern Ireland Protocol, by leaving NI in the EU, has pushed it into the constitutional equivalent of a granny flat.