This book is the reworking of a PhD thesis, and it shows. The starting point is a challenge to the theory that the IRA was brought to heel by the intelligence agencies, which had infiltrated the movement to the point that it could no longer function. There is some reason to believe this may be true, but it’s hard to prove.

The supposed head of the IRA “nutting squad” is under investigation now as the alleged agent Stakeknife. You don’t do much better at taking over the reins of a paramilitary organisation than to recruit the head of security. Gerry Adams’s car and office were both bugged, and the Sinn Fein head of administration Denis Donaldson was an agent too.

Thomas Leahy acknowledges that he