In 1913, Maj. Charles Rhodes explained to a sympathetic audience[1] that the notion that airplanes had made cavalry irrelevant was "such an absurdity as to hardly merit consideration" (46). But Rhodes was no conservative cavalryman resisting technological transformation. He believed that advances in aircraft would improve the Army's reconnaissance capabilities without necessarily rendering cavalry irrelevant. Likewise, it is the thesis of historian Lori Henning's Harnessing the Airplane that cavalrymen were rational "resisters" rather than inflexible reactionaries (5). Henning (St. Bonaventure Univ.) explores in detail how British and American cavalrymen thought about and experimented with aircraft and, secondarily, tanks.

Henning, a historian of military technology, seeks to reorient teleological discussions of technological advances in order to clarify the complex relations between individuals, institutions, and relevant evolving technologies (156). Concomitantly, she considers instances of "failed technology" (4) to add nuance to our understanding of successful developments. Henning also seamlessly interweaves analyses of the greater role of identity in transforming British, as opposed to American, cavalry.

In chapter 1, "State of Affairs," the author states her intention to closely compare US and British cavalry. She establishes that British cavalrymen considered their chief role to be providing shock troops on the battlefield. Hence, they had few reservations about ceding what they considered the subsidiary role of reconnaissance (21). By contrast, US cavalrymen—who used horses for mobility, fought dismounted (9), and harbored no romantic notions of daring cavalry charges—found it harder to jettison traditional responsibilities, including reconnaissance; this may explain why the US cavalry mechanized more slowly than the British (145).

Chapters 2–3, "Early Response to Heavier-Than-Air Flight" and "Developing a Relationship in the 1920s," respectively, concern the close ties between aviation and cavalry in the United States and Great Britain. After World War I, both countries increasingly counted on airplanes for strategic reconnaissance and cavalry for tactical reconnaissance; the US Army also divided responsibilities in doctrine as well (84). But aviation and cavalry remained closely interdependent: the US Air Corps Tactical School supported cavalry through the 1930s (78, 114). Henning depicts airmen, not cavalry, as increasingly uninterested in combined operations, while British airmen had already acquired independent service status in 1918 (79–80). And too, by the late 1920s, aviation began to dominate cavalry (85). As the United States and Britain embraced strategic bombardment, cavalrymen realized they needed their own aviation capacity. Thus, in the 1930s, they turned to autogyros[2] (122–23), which could travel at slow speeds without stalling and land on shorter runways (chap. 5).

Chapter 4, "National Economy," concentrates on the overarching effect of British economic conditions on cavalry's future (111), as the nation sought to decrease its military spending significantly in the 1920s and 1930s. Henning also debunks certain airpower myths, particularly the idea that airplanes alone could police the empire on the cheap (87). She says little about cavalrymen's willingness to incorporate aviation until her conclusion (144), when she announces that the "vast majority" were favorably disposed. Yet she never specifies what percentage of cavalrymen embraced the change or welcomed combined operations with aircraft (155). Tami Davis Biddle[3] has shown that a certain cognitive dissonance shaped British and US airmen's response to new technology. One wonders how cavalrymen escaped such dissonance during an existential crisis. Henning, moreover, identifies the cavalrymen's embrace of technological change as a matter of forward thinking rather than self-interest.

Still, the author moderates her picture of cavalrymen as "overly optimistic supporters of modern weapons" (7) by highlighting the decades it took for change to be institutionalized: "Rather than criticize cavalrymen's lack of vision about the future impact of airplanes and mechanization or their attachment to horses, it is better to understand the cavalry's experience with airplanes during the more than thirty years the two coexisted" (147). For example, cavalry, unlike aircraft, could provide reconnaissance during bad weather or at night (46, 67).

Harnessing the Airplane will intrigue and enlighten anyone interested in how militaries adapt—or not—to innovation and change, especially amid economic hard times. Lori Henning astutely charts a decisive shift in favor of machines over men by the 1930s: "The argument that the man (and the horse), not machines won wars, so common in the military and the public in the 1920s, dropped in visibility by the 1930s except in the writings of cavalrymen" (140). In making that case, she has implicitly shed light on the effects of the present-day military's use of, for instance, robots, drones, and artificial intelligence.