The Squad is an account of the intelligence war waged principally in Dublin, by Michael Collins and the IRA from January 1919 to the Truce in 1921. It is based on a series of interviews given by participants to the Irish Bureau of Military History on the proviso, for many, that they would only be released after the interviewee’s death.

The author does not spend much time contextualising the violence in the politics of the time clearly having decided that, as there are many other books which provide such context, he has little additional to offer. This means that one is pitched almost straight away into the minuatae of intelligence operations with a bewildering array of characters.

However patience with this approach pays dividends: the book conveys the mammoth scale of the intelligence operation Collins undertook and hence the centrality of this in undermining Britain’s capacity to hold Ireland. The book also provides insight into how the ruthlessness and secrecy of the operations led to the moral erosion of some of the Squad members whose subsequent military and democratic conduct was far short of the ideals initially outlined by Collins for them.

Collins insisted that revenge was never to be part of the conduct of the Squad, leading many of the shooters to presume that killings such as that of Lee-Wilson, who had maltreated Tom Clarke after the 1916 Rising, was principally an act of military necessity, rather than an act of revenge. However as generally the shooters were simply given orders to kill not the reasons for the killings there is little substantive illumination on the reasons for some of Collins’ more controversial killings.

Certainly as the war wore on into late 1920 and early 1921 there is a sense that the routinisation of killing led to a toleration of revenge and reprisal comparable to that shown by Lloyd George and his Cabinet in their conduct of the war: Todd Andrews, later a distinguished Irish public servant, who participated in a support role to the Squad in the Bloody Sunday operation in late 1920, noted how the behaviour of some of his comrades resembled that of the Black and Tans.

And, however justifiable was this campaign, the author does not allow the reader to lose sight of the fact that it resulted in the killing, often brutal, of other human beings: in the Squad’s first assasination, of a political detective Patrick Smyth, they used .38 calibre weapons, which they discovered could not dependably put a man down – Smyth struggled on in pain and fear for a long while after the first bullets hit; the assasination of 22 year old District Inspector Phillip O’Sullivan in front of his fiancee, clearly bothered his killers so much in later life that they could not bring themselves to speak of it.

Nevertheless, in spite of the sense of excess towards the end of the war, the book does confirm a general tendency of restraint and growing democratic sensibility by Collins that compares favourably with many of his contemporaries in British or American politics. The experience of the pity of war seems to have been a major factor in Collins’ own growth as a statesman. His loss continues to cast a long shadow on twentieth century Irish history.