Northern Ireland 's police forces – especially the USC , which was almost exclusively Protestant and unionist – were implicated Bodily_harm in a number of attacks Attack on Catholic and Irish nationalist civilians as reprisal Revenge for IRA actions .

The Irish War Hostile_encounter of Independence ( ) or Anglo-Irish War Hostile_encounter was a guerrilla war Hostile_encounter fought Hostile_encounter in Ireland from 1919 to 1921 between the Irish Republican Army ( IRA , the army of the Irish Republic ) and British forces Military_operation : the British Army , along with the quasi-military Royal Irish Constabulary ( RIC ) and its paramilitary forces Military_operation the Auxiliaries and Ulster Special Constabulary ( USC ) .