Historians generally view the period of internment as inflaming sectarian tensions in Northern Ireland , while failing in its goal of arresting key members of the IRA . Many of the people arrested had no links whatsoever with the IRA , but their names appeared on the list of those to be arrested through bungling and incompetence . The list 's lack of reliability and the arrests that followed , complemented by reports of internees being abused far in excess of the usual state violence , led to more nationalists identifying with the IRA and losing hope in non-violent methods . After Operation Demetrius , recruits came forward in huge numbers to join the Provisional and Official wings of the IRA . Internment also led to a sharp increase in violence . In the eight months before the operation , there were 34 conflict-related deaths in Northern Ireland . In the four months following it , 140 were killed . A serving officer of the British Royal Marines declared : It ( internment ) has , in fact , increased terrorist activity , perhaps boosted IRA recruitment , polarised further the Catholic and Protestant communities and reduced the ranks of the much needed Catholic moderates . In terms of loss of life as well as number of attacks , 1972 was the most violent year of the Troubles . The fatal march on Bloody Sunday ( 30 January 1972 ) in Derry , when 14 unarmed civil rights protesters were shot dead by British paratroopers , was an anti-internment march
Bloody Sunday
Bloody Sunday (1972)
Operation Demetrius