The visit of Under Secretary of State Sumner Welles to four European capitals in early 1940 has long been an issue of historical contention. Was it a genuine – if naive – peace effort, or was it a more cynical attempt to delay the inevitable conflict brewing in Europe? Yet curiously, at the same time as the Welles mission has yielded different interpretations, it has never been the subject of a historical monograph. In filling this gap in the literature, J. Simon Rofe explores the motivations behind the Welles mission in great detail. His analysis is based on a range of archival materials, some of which were previously unavailable to scholars, most notably the papers of Welles himself.

Overall, Rofe highlights the interplay of four main objectives behind the mission: “the exploration of a peace compatible with American terms; the gathering of firsthand information through a personal envoy; prolonging the phony war; and perpetuating Italian neutrality” (2). The emphasis on exploration in the first objective is important. It is made clear that this was no naive mission bent on achieving peace at any cost. Instead, it was immediately clear that no such peace compatible with American terms could be found, and the objectives evolved during the mission. However, Rofe also makes it clear that the objectives were never explicitly spelt out, revealing the surprisingly speculative nature of Welles's visit.

More broadly, Rofe highlights four themes throughout the text – the pivotal role of Welles, the limited but still crucial role of Secretary of State Cordell Hull, the domestic and international constraints on US policymaking, and the influence of Anglo-American relations on the Welles mission (and vice versa). While the emphasis on Anglo-American relations initially appears to sit awkwardly with the otherwise American focus, Rofe successfully weaves the theme into the narrative and undermines any notion of a prewar “special relationship.” Nevertheless, the question remains as to why US relations with France, Italy and Germany do not merit similarly detailed attention here.

A few wider questions merit further consideration, particularly in the sphere of domestic politics – to what extent was Roosevelt countering claims of warmongering as he moved towards an unprecedented third election? Also, what does the mission tell us about Roosevelt's broader foreign-policy aims at the time? Nevertheless, this book is a valuable addition to the historiography of US foreign policy on the eve of World War II.