In recent years historians of contemporary science have focused more on the 1970s, since there is a growing consensus that this was a decade of dramatic change for the scientific community worldwide. In this book readers will find a convincing motive for this transformation, namely the growing conflict among US researchers over the nature and ambitions of science, especially in relation to its military applications. Bridger admirably examines the confrontation between those scientists no longer willing to (even indirectly) contribute to the production of new weaponry and those who instead continued to support new schemes elaborated by the US administration and its defence branches. The book thus follows the activities of two competing figures: the agitator who used the knowledge acquired on certain weapons systems to criticize government decisions about their uses, and the government adviser who, especially following the denunciation of colleagues in the public arena, took these controversial issues back to the corridors of power to find viable solutions.

Scientists at War focuses especially on the pivotal role of the Vietnam conflict in framing an ethical debate on weapons research. While it was nuclear testing in the early 1960s (discussed in Chapter 2) that set the circumstances for a first wave of concerns and protests from within the scientific community on what scientists should research (or abstain from studying), it was the new array of chemical weapons used in South East Asia that led to a long-lasting debate. As shown in Chapters 3 and 4, this debate also informed the proceedings of the US President's Scientific Advisory Committee (PSAC), the chief advisory structure overseeing government policy on scientific research. We thus learn about the marginalization of science advisers such as George Kistiakowsky, who vibrantly opposed the use of Agent Orange and paid the price for this opposition by having to resign from the committee.

The conflict over the ethical dimensions of weapons research radicalized the scientific community. Some scientists decided to abandon their studies, refusing to be complicit, while others looked for solutions through the design of innovative weaponry. Bridger examines these compromises as distinctive of the Jasons, the high-powered advisory group of scientists which featured in Lyndon Johnson's administration. She reveals that while their efforts might have been genuine, the construction of a space for advice virtually removed from the public eye stirred controversy and further exacerbated science activists organized under the recently established Scientists and Engineers for Social and Political Action (SESPA).

The debate thus continued without offering viable solutions to the mounting conflict on ethics. Chapter 5 sets the scene on the MIT campus to document yet another struggle between defence-contracted scientists at the Instrumentation Lab and local grass-roots protesters, while the following chapter focuses on the contrasts emerging in the American Physical Society, where a SESPA group was also active (and outspoken). The ethical ‘malady’ affected many prestigious US laboratories and the activities of prominent academics such as Thomas Kuhn and Noam Chomsky. These concerns thus elicited further historical and philosophical reflections on the level of autonomy of contemporary science and its ‘neutrality’.

The repercussions of the fight over weapons research were long-lasting too, as they defined the PSAC's fall. Although Nixon kept it running, he pushed it to the periphery of the White House advisory structure. The shake-up had long-lasting effects as it set the circumstances for making university researchers less willing to contribute to weapons-related studies and at the same time empowered those in the private sector as chief contributors to military-related research. US scientists who felt marginalized and overlooked in government circles eventually ended up opposing Ronald Reagan's Star Wars project (examined in Chapter 7) and formed a united front against government plans for the controversial defence system.

To sum up, this book has the great merit of blending historical narratives of radicalism and government advice distinctive of the US scientific community in recent years. It successfully shows that the conflict about ethical approaches to weapons research left few winners, but forced the administration and patronage of American science to change. That said, these scientists ‘at war’ hardly ever appear to interact with colleagues from other countries, so that the portrayal of the debate on weapons research makes it look almost entirely a US affair. It would have been interesting to follow its ramifications into US-led transnational agencies such as NATO, into the activities of scientist-led international organizations advocating arms control such as Pugwash, and into those of many other set-ups contributing to internationalize science during the Cold War period. But even so, Scientists at War casts new light on incredibly important, yet under-studied, issues regarding the recent history of the US research establishment. It helps us to better understand how important decisions on new weapons systems were taken by a few policymakers in isolation, or thanks to the advice of a few science advisers, while the debate on their use and effects raged on at the core of the US research community. During the 1970s the ethical debate on weapons research warped many research careers. And, more significantly, it dramatically changed the landscape of American science for the following decades.