The subject of special operations in the Second World War is rarely treated with a critical or analytical eye. Michael Dilley attempts here to correct this by offering "discussions and critiques of the employment of various special purpose, special mission units during World War II" (15). The twenty-three chapters of Behind the Lines describe a number of special operations units and their missions, then provide a "mission critique" of each. Dilley has divided his work into two unequal sections: "Behind Enemy Lines" (twenty chapters) and "Behind Friendly Lines" (three chapters). The selected the units and operations reflect his broad defining criteria for "special purpose, special mission organisation[s]" (15). It is refreshing to see both Axis and Allied special operations included, some of which fall outside the well known "great raids" so often discussed in the literature of the subject.

The Second World War witnessed a proliferation of special and elite units with particular mandates. These formations, with various degrees of institutional legitimacy, served in virtually every theater of war and in diverse operational and strategic circumstances. Despite Dilley's assertion that his selection method "was not capricious or haphazard" (19), the choice of missions and units is very eclectic.

Except for the three rather awkward "Behind Friendly Lines" chapters, the volume proceeds more or less chronologically, beginning with an early 1941 raid in Italy and ending with a 1945 airborne operation in Burma. Dilley indicates no particular rationale for choosing operations and readers may be surprised by the absence of some especially notable examples. And, too, the decision to start in 1941 means omitting several significant actions earlier in the war, most notably the classic German glider-borne attack on Eben Emael in 1940.

Those familiar with the book's subject will also miss coverage of certain units with formidable wartime reputations, such as the Long Range Desert Group or OSS (Office of Strategic Services) Detachment 101, as well as many missions of the British Army/Royal Marine Commandos and the US Army Rangers. One wonders, too, why so many units are ignored or glossed over while three whole chapters are devoted to the Alamo Scouts. Dilley does write that "For a variety of reasons … the Alamo Scouts are America's quintessential special operations forces of World War II" (162). This is true enough, but, as they were a relatively small formation, their high value might have been made more apparent through a broader selection of units for comparison.

Another peculiarity of the book is its heavy stress on airborne units, which, despite their elite light infantry credentials, are not always considered to be special operations forces at all. The author's own background as a paratrooper may explain the inclusion of several chapters focused on airborne actions like Operation COLOSSUS against Italy in 1941, the raid on the Los Baños prison camp in the Philippines in 1945, Japan's use of airborne troops to seize the airfield and oil refineries at Palembang in 1942, and the British attack on the Merville Battery on D-Day.

Some chapters treat the nontraditional use of airborne assets, as in the Soviet last-ditch deployment of "Locust Warrior" paratroops in early 1942, or the use of the African-American 555th "Triple Nickel" Parachute Infantry Regiment to fight forest fires started by Japanese balloon bombs in the United States. These do not accurately represent the purposes to which airborne forces were typically put in the Second World War. Such units for the most part fought in a relatively conventional manner, albeit as light infantry. This point may be lost on the general reader. Since airborne forces were often manned and used on a different scale from the other special forces Dilley discusses, it would have been good to create a discrete section for them.

Each chapter is followed by a "mission critique" based on the author's own judgment and, more problematically, on standards developed by William H. McRaven and Lucian S. Vandenbroucke.[1] Because the work of McRaven, excellent in itself, concentrates on direct action raids, it is not entirely relevant to the evaluation of more nuanced forms of special operations activities, for example, intelligence gathering or working with partisans. Vandenbroucke also adopts a coup de main focus, but his preoccupation with US failures during the Cold War makes it harder to apply his findings to special operations in the Second World War. In short, Dilley should have developed his own terms of evaluation.

Choice of assessment criteria aside, the author's evaluations are often unfair and counterfactual. For instance, in his mission critique of operation BITING, the February 1942 Bruneval raid, Dilley unhelpfully comments: "Perhaps the only thing lacking in this operation was something that was not available then; namely a heavy-lift cargo helicopter..." (77–78). Similarly, concerning Operation FLIPPER, the failed November 1941 attempt to assassinate Gen. Erwin Rommel, he states that there were "so many varied alternatives available … such as by an aerial bombing (à la [Muammar] Ghadaffi), or by a sniper, or by a command-detonated or time-delayed bomb, the use of special operations forces here should have been questioned" (46). But these "alternatives" were ridiculously unrealistic given the situation in North Africa at the time. Just how, for example, would the putative sniper have been inserted in a position deep behind enemy lines?

Other evaluations are too narrow and self-evident. For instance, Dilley attributes the success of the Bruneval raid to the absence of security breaches (78). Does this not go without saying for any successful operation? A discussion of the importance of operational security would be much more appropriate in accounts of clear failures (such as during the disastrous Operation AGREEMENT of September 1942—not featured in this work). Basic requirements for any effective mission would be better identified in a general introduction or conclusion.

Another problem is posed by the extreme brevity of some chapters, which leaves too many questions unanswered. For instance, in discussing the Tragino aqueduct raid, the first ever operational use of British airborne troops, Dilley states that "Good lessons for future operations came from this raid. Probably most noticeable was the increased number of volunteers who wanted to join the parachute forces" (38). But the reader is told neither what these "good lessons" were nor that the action had the undesirable effect of promoting a "raid focus" for British airborne forces, to the detriment of the military effectiveness of their deployment in Operation TORCH.

Far too much of the limited space in the shorter chapters is given over to the minutiae of force structure, training regimes, and unit insignia. This at the expense of fuller analysis of whether units should have been raised in specific formats and the extent to which they affected the course of the war on tactical, operational, and strategic levels. For instance, one chapter concerns the SOE/OSS Jedburgh teams deployed mostly in France after D-Day in a complex undertaking involving about a hundred different missions. But Dilley devotes only four pages to the operational deployment of these varied teams, contenting himself with sweeping statements such as "[Jedburgh team] HUGH did better than the SAS BULLBASKET [sic, read BULBASKET] team that accompanied it into France; the SAS operation was virtually destroyed by the Germans" (171). The reader is given no clue that the value of BULBASKET is a subject of intense scholarly debate.

The book is also marred by outright errors. Dilley writes that "the SAS emulated the Jedburgh idea in France and Italy" (175), but the SAS predated the Jedburghs and was acting in France with a different modus operandi. In the chapter on the Gran Sasso Mussolini rescue, the author claims that Otto Skorzeny's men were "Germany's first special forces, patterned after the British Commandos" (215). But the first German special forces unit of the war was the Brandenburger Regiment; furthermore, Skorzeny's unit was nothing like the British Commandos in either purpose or composition.

The four-page chapter on the British airborne attack against the Merville Battery on D-Day begins by stating that

However, the British airborne forces on D-Day were oriented toward vertical envelopment, securing specific objectives, and protecting the eastern flank. The Merville Battery action was a sudden strike against a specific objective, not an effort to cause general disorder. Two pages later, Dilley himself writes that "The battle at the Merville Battery would eventually take its place among the finest actions ever undertaken against a specific objective" (179).

The OSS Operational Groups (OGs) were among the most interesting US special operations forces of the war. And they clearly influenced the postwar resurgence of American special operations capabilities. Dilley's one short chapter on the "Operations Groups" (sic) omits many significant details, since he concentrates narrowly on the NORSO (Norwegian Special Operations) group. Ignoring the fact that some of NORSO's men had served during the invasion of France, he offers only an uncritical summary of their March-May 1945 deployment in Norway, with no discussion of whether that relatively costly mission to a strategic backwater at war's end was worthwhile.

These various shortcomings of Dilley's book are symptoms of a dearth of primary source research, except for a handful of interviews and/or correspondence with veterans to flavor his narrative. Furthermore, many of the secondary sources Dilley has consulted are badly outdated, betraying the origins of some of the book's chapters in magazine pieces published in the 1990s and earlier. Source citations are extremely uneven as well: the bibliography for the strong chapters on the Alamo Scouts dwarfs that of all the other chapters. Indeed, the chapter (largely disconnected from the book's leading themes) on Office of Naval Intelligence agent Willis D. George, who was charged with breaking into foreign consulates in the United States, is supported by a single source—George's own book published in 1990.

Given the heterogeneous nature of the book, it would have benefited from a unifying statement of conclusions, perhaps in an epilogue, about, for example, the number of units raised; the cost-effectiveness of various operations; the advisability of assigning units overlapping responsibilities; and whether there were differences in the conduct of special operations from country to country. In the absence of such conclusions, readers are left to guess at the overall value of special operations. The book ends abruptly with two appendices, one listing (with no indication of rationale) those operations and units "deserving special recognition."

In fairness, Behind the Lines has its merits. It is written in the easy and confident style of a man with a military and intelligence background, a boon to students and general readers. The inclusion of special operations of different nationalities is laudable, as is the widening of purview beyond raiding operations alone. Dilley also avoids the pitfall of proclaiming special operations to be a decisive, war-winning weapon. These virtues notwithstanding, scholars and experts in the field will be disappointed by the lack of more perceptive critiques and the motley assortment of cited secondary literature. The subject of special operations in the Second World War still requires a more systematic and critical scholarly evaluation.