 As Chief Military Officer he faced the opening of the Irish War of Independence; in August 1919 he prohibited an Irish Nationalist procession from marching on the city walls of Derry, fearing that grave disorders would occur.However Hacket Pain sometimes resisted pressure.In January 1919 Dawson Bates wrote to Sir James Craig telling him that Hacket Pain was reluctant to bring out troops against Sinn Féin-inspired strikes in Belfast, or to do anything that might make the workers think they were being intimidated, despite pressure from people Bates described as "scare-mongers".