“This was a dirty, filthy war,” Richard O’Rawe says, and few things during The Troubles were filthier or dirtier than the activities investigated by Operation Kenova. Kenova was an investigation into what its official website rather obliquely refers to as “a range of activities surrounding an alleged individual codenamed Stakeknife”. But the range of activities was brutal and grim. Stakeknife — Freddie Scappaticci — was a leading figure in the IRA’s Internal Security Unit (ISU), which the provisionals set up in 1978 to investigate informers. Scappaticci was himself a British agent and the interim Kenova report, which did not officially…