“It is disappointing that the deep and overlapping anti-Irish and anti-Catholic bigotry of so many DUP-supporting unionists appears to still play a significant role in Northern life and politics.” Above, DUP leader Arlene Foster.    Photograph: Paul Faith/AFP/Getty Images

How much did continuing religious bigotry have to do with the collapse of the Northern Ireland Executive last month? It was clear from Martin McGuinne(...)