In July 1941, President Franklin Roosevelt appointed William Donovan to head the future Office of Strategic Services (OSS) and gave him a broad mission encompassing intelligence, special operations, and propaganda. In April 1942, Donovan activated Detachment 101, the first American special operations unit of World War II. Historian Troy Sacquety (US Army Special Operations Command) tells the unit's story from start to finish for the first time. While several veterans of the unit wrote memoirs, these focus primarily on high adventure and brave sacrifice—what the unit actually did. Sacquety pushes the analysis deeper, asking precisely how Detachment 101, as an organization, carried out its mission. Although his narrative is generally chronological, he carefully isolates the unit's various functions and examines their development.

Detachment 101 faced a difficult start. It received virtually no useful information from Washington before it arrived in Gen. Joseph Stilwell's China-Burma-India (CBI) Theater to conduct sabotage in northern Burma. Once there, it was confronted by soldiers who did not understand that its military personnel were detailed to a civilian organization. Stilwell was initially skeptical, but, having only the British V-Force for intelligence collection, he could not afford to pass up additional clandestine forces. Likewise, London was not keen on Americans in its colonial possession, but, lacking the resources to retake Burma alone, accepted US assistance. William Peers, the unit's second commander, described its mission as conducting "all operations which [Allied forces] are not prepared to undertake" (126). Given their small initial complement of only twenty-one officers and enlisted men, Detachment 101's members often had to assume multiple roles.

Sacquety paints a picture of a unit continually reforming and adapting. He outlines four phases of its operations: infiltration, subversion, guerrilla warfare (as originally conceived by Donovan on the British Special Operations Executive [SOE] model), and, by mid-1945, conventional combat actions, since it was by then the only US ground combat force in Burma.

Detachment 101's flexibility was necessitated by the neglect of OSS Washington and the light touch of General Stilwell. Its men were left to achieve their mission as they saw fit. This was fortuitous, since Washington was focused on Europe, a totally different environment from Burma with very different requirements. Following a visit to the Detachment in December 1943, Donovan secured greater support for the unit without compromising its autonomy. Within the unit, Peers ensured that area commanders had control of operations, intelligence, and communications.

Another hallmark of Detachment 101's flexibility was its tight integration of disparate elements—"The 101 show is a unified one" (167), as one of its members put it. Beginning with the original core group itself, Detachment personnel often came from the Special Operations (SO) branch; they consistently performed the duties they deemed most pressing, not necessarily those of their officially assigned branch. Even when, later in the war, branch distinctions existed on paper, personnel were blended together, as visitors from Washington often observed. As Detachment 101 received new branches, such as Morale Operations (MO), Peers took pains to assimilate them into the existing structure rather than merely tack them onto it.

From its earliest days, Detachment 101 liaised extensively with neighboring units. Upon arriving in the CBI Theater, Carl Eifler, the unit's first commander, met with Colin Mackenzie, the SOE commander in India. They agreed that, as the senior covert organization in theater, SOE should have first choice in recruiting agents and assigned a liaison officer to ensure coordination. This early support "proved critical to getting Detachment 101 operational" (24). In 1944, the arrangement was formalized with the creation of P Division, a board representing all British and US intelligence, special operations, and propaganda organizations in the theater. Although the Americans feared P Division was designed to bring their activities under British control, it proved useful for sharing information and deconflicting missions. There were, naturally, hiccups along the way. The OSS was not notified in advance of the first Chindit expedition into Burma and one group of men had their covers blown by the British before they ever reached the field. But, on the whole, local British commanders were helpful, providing weapons, supplies, and personnel. Detachment 101's Maritime Unit (MU) benefited from its relationship with SOE's maritime element and the captains of certain small Royal Navy vessels.

Detachment 101 forged a strong relationship with the US Army Tenth Air Force, to which, beginning in 1943, it provided weather reports, early warnings, targeting information, and bomb damage assessments, as well as—most importantly—picking up pilots downed behind Japanese lines. As a result, Detachment 101 enjoyed frequent use of aircraft for its drops to groups in the field. Moreover, OSS liaison officers and radio operators who lived alongside their USAAF colleagues ensured top priority for Detachment 101, which eventually provided the Tenth Air Force with 90 percent of its intelligence.

Liaison officers with Detachment 101 also served on the staffs of Gen. Orde Wingate's second Chindit expedition, Col. Frank Merrill's Marauders, and the US First Air Commando. It provided the Chindits with Nisei translators and acted as the communication conduit between Wingate and Stilwell, who lacked a liaison contact with the second Chindit expedition. Detachment 101 also communicated with British intelligence's detention facilities, the British Ministry of Information in New Delhi, and the Burma Police Intelligence section.

Special Operations were the bread and butter of Detachment 101, initially involving high-risk, long-range penetrations into Japanese-occupied territory. Owing to limited intelligence and poor training, five of the first six inserted teams were captured. The Detachment learned from its early mistakes and shorter-range operations became the norm. Rigorous contingency planning, air reconnaissance, and pathfinder units now preceded all missions before larger units were deployed. Moreover, having to rely on the British taught the Detachment that it needed its own organic transportation. Peers also instituted debriefings after every mission to ascertain best practices for future actions.

Guerrilla warfare, too, came to typify Detachment 101 operations. For most of the war, tribesmen were recruited from among the Kachins, a hill people loyal to the British. The Americans engaged local leaders and ensured good rapport by paying recruits, supplying basic items like salt and cloth, and providing medical treatment. The latter was particularly important, convincing the Kachins that their wounded would have access to good care. These militant tribesmen, culturally accustomed to hit-and-run tactics, furnished the OSS with an ideal manpower pool. As the war progressed, Detachment 101 rapidly established indigenous intelligence networks and raised guerrilla forces wherever they went. By 1945, the unit comprised a thousand British and American personnel and more than ten thousand guerrillas. So effective were OSS operations that, by the end of 1943, Japanese troops routinely resorted to traveling by night. The efficiency of Detachment 101, particularly in the final year of the war, beggars belief—by conservative estimates, it inflicted twenty casualties for every one it sustained. Air strikes called in by OSS killed additional enemy personnel.

Although intelligence was not initially part of Detachment 101's charge, Peers recognized both an opportunity and a need. When the first Chindit expedition neared Myitkyina in spring 1943, OSS elements in the area, having completed an unrelated sabotage mission, remained in place and provided intelligence to their British counterparts for several months. A Secret Intelligence (SI) section was formed in January 1944 to oversee the intelligence work that Detachment 101 personnel were already doing; it coordinated collection efforts and matched the intelligence with users outside of OSS. That same month, the Detachment received its first personnel from OSS's Research and Analysis (R&A) Branch. While R&A mostly supported strategic-level intelligence, Detachment 101 integrated the new analysts into tactical collection and operations to produce assessments for immediate use. By assisting in imagery analysis, cartographic support, prisoner interrogation, and other functions, R&A personnel not only won friends but also produced integrated intelligence based on a variety of sources. So valuable was Detachment 101's intelligence for Allied forces that it provided daily updates to thirty-five different organizations.

Detachment 101 also included an MO section, which used information secured by debriefing captured Japanese soldiers to divide the Japanese from the various ethnicities of Burma. While the section initially suffered from staffing problems and poor relations with the Office of War Information, it eventually developed useful working relationships with other OSS elements in the theater and successfully encouraged Japanese surrenders.

In February 1945, Detachment 101 received responsibility for the Arakan Field Unit (AFU), which conducted maritime operations along Burma's southern coast. In typical fashion, patrol boats were integrated with light infantry Operational Groups and intelligence and MO personnel to create a flexible amphibious reconnaissance capability.

Arguing that special operations entail more than just field units, Sacquety also considers various aspects of Detachment 101's administration, including training. When the unit arrived in northeastern India, it established a jungle warfare school for its members, who practiced various elements of their tradecraft. Following the example of the British Camp X in Canada, where many of the earliest OSS members had trained, students honed their skills by infiltrating Allied installations. The Detachment eventually formed its own schools and training section, which worked closely with SO to ensure that lessons learned in the field were incorporated into the program. Detachment 101 continued to conduct its own training late into the war, since it considered general OSS preparation inadequate for newcomers to the Burmese terrain, which was far more challenging than anything faced by European veterans. True to its collaborative spirit, Detachment 101 also prepared personnel for other units in theater.

While many OSS formations contributed to the war effort, Sacquety argues that Detachment 101 was the only one whose operations were critical to the theater where it served. Since it remained in place for three years—the longest period of service of any OSS unit—it gained an unrivalled knowledge of the geography and local populations. Although Detachment 101 was disbanded in July 1945 with much of its personnel transferred to China and is not officially recognized in the lineage of any Army unit, Sacquety contends that it was the forerunner of today's US Army Special Forces. He notes that one of the founders of the Special Forces, Martin Waters, was a Detachment 101 veteran and that, more to the point, the two organizations share strong similarities with regard to mission and culture.

While Sacquety's account generally avoids historiographical polemics, he does not shy away from the occasional criticism. The British could be squeamish about the role of foreigners in their territory. OSS Washington was frequently out of touch with and inattentive to the needs of its men in Burma. Bill Donovan, though a visionary, was a poor administrator. And the much-celebrated Chindits and Marauders, though they made meaningful contributions, have received too much credit, sometimes at the expense of Detachment 101.

Readers seeking thrilling combat stories may be disappointed by The OSS in Burma, though it certainly evokes the local color of war. But those interested in the real challenges of organizing successful special operations will find a wealth of insight in Troy Sacquety's work.