Last August's shooting of a young Catholic, Loughlin Maginn , was the 2,744th murder since the present Northern Ireland troubles began. But it will be remembered as the killing which triggered off a damaging row between the governments of London and Dublin. Maginn was targetted and murdered by Protestant terrorists using an intelligence file leaked from within forces there to prevent such violence. Next month a report on the collusion betweenLoyalist paramilitaries and dissidents in the army and...