Moral reform is a familiar theme in the historiography of the United States. That well-intentioned social improvers, often animated by worldly Protestantism, worked to tame the social ills that capitalist modernity nourished is well established. Themes such as temperance, anti-prostitution, and religious evangelicalism are well known to historians. Thus far, however, the nation-state has largely framed our understanding of the late nineteenth-century reform era. This is where Ian Tyrrell breaks new ground. Reforming the world breaches the confines of national historiography and reveals moral reform to have been a project that was global in its aspirations, transnational in its reach, and even imperial in its implications.

Focused as it is on American historical actors, the book contributes to the globalization of American history, a project to which Tyrrell has already made important contributions, including the interpretative synthesis Transnational nation (2007). Unlike that book, Reforming the world is less a manifesto than a fine-grained history of social movements and reformers. Here Tyrrell has written a detailed and substantive history in which flesh-and-blood human beings predominate. The missionaries Margaret and Mary Leitch, the temperance activist Wilbur Crafts, the Episcopalian churchman Charles Brent, the YMCA leader John Mott, and the journalist William ‘Pussyfoot’ Johnson are among the colourfully rendered characters who cross borders and build transnational networks in pursuit of social uplift and reform. This careful approach brings major dividends: by delving into lives lived and struggles waged, Tyrrell shows how transnational social reform played out in practice and substantiates the claims that he and others have made for transnational approaches to American history. If there is a cost to this approach, it will be borne mainly by casual readers, who may miss the novelty of a subtle argument that is more woven into the narrative than boldly asserted.

Global and transnational historians with interests far removed from the history of social reform will also find much here with which to engage. One of Tyrrell’s deftest accomplishments is to relate the lives of activists and reformers to the history of globalization. That the involvement of Americans in the larger world has evolved over time, often in relation to changing material circumstances, is one of the book’s important insights. Tyrrell shows us how the 1870s and 1880s thickened and accelerated the material infrastructure of globalization, with crucial implications for the work of transnational moral reform. International communications facilitated the networking of transnational reform societies; transportation networks encouraged the voyaging of individuals such as Mott, who ‘crossed the Atlantic over one hundred times and the Pacific fourteen times’; while periodicals such as National Geographic brought the world home for Americans who had yet to see it for themselves. Americans did not create the globalizing infrastructure society of the late nineteenth century, which centred upon western Europe, but they were acutely, perhaps uniquely, open to its possibilities and opportunities.

The moral reformers whom Tyrrell follows are a diverse group. If any single commitment united them, it was their determination to combat social vices. The Leitch sisters, for example, involved themselves in international efforts to promote the prohibition of alcohol and to curtail the use of drugs such as opium, the abuse of which they encountered in Ceylon. The Leitches considered themselves anti-imperialists; other reformers embraced America’s annexation of the Philippines after 1898 as an opportunity to expand the reach of moral reform. The National Christian Citizenship Convention under Wilbur Crafts, for example, focused its efforts after 1898 not on combatting empire but on the abolition of the ‘military canteen’ in the Philippines, arguing that provision of alcohol was corrupting not only to American troops but also to the Filipinos whom the Americans were supposed to be uplifting. For all the implicit paternalism, some reformers exhibited a strident, even radical, racial liberalism. Americans and Filipinos were basically alike, Crafts and others argued, susceptible to the same vices and thus needful of similar protection. The state was a focus throughout. Reformers took sharp umbrage at even implicit government sanction of corrupting activities, from the military brothel to regulated prostitution. What they sought was ‘to create a moral state and a moral empire’ (p. 124).

The empire question is among the trickiest with which Tyrrell grapples. What was the ‘moral empire’ that the book’s subtitle evokes? Did it resemble or repudiate Europe’s colonial empires? What were its consequences for the United States in the world? To address this conundrum, Tyrrell turns to another character, Antonio Gramsci, who mused from his prison cell upon the capacity of cultural power to sustain international hegemony. For Gramsci, the stakes were clear, as was the capacity of capitalism to sustain itself in the cultural domain. However, he also believed that cultural power served an instrumental purpose, and it is not clear whether Tyrrell accepts the underlying critique of hegemony that Gramsci offered and which critical historians of capitalism and of American power still echo today. So the question remains, what kind of empire was the American empire? Was it benign, malign, or something in between?

Tyrrell’s vision of American empire is ultimately more seductive than Gramsci’s: an imperial project, certainly, but one predicated on visions of fraternal responsibility, moral and social uplift, and even racial egalitarianism. So where did this moral empire lead? Did it prefigure the superpower role that the United States would assume later? Or was the moral empire of the late nineteenth century a historical dead end, an empire of persuasive influence far removed from the more coercive empire that the United States would build in the era of the Cold War? It is a testament to Tyrrell’s accomplishment that a book so carefully grounded in the sources also opens such challenging questions and, in doing so, encourages us to contemplate the history of American power from unfamiliar vantage points. This is an important book, and it addresses a broad range of topics – from social and cultural globalization to American power. Its achievement is to demonstrate that the transnational turn in American historiography can sustain not only stirring manifestos but also revealing research agendas that themselves pose interesting questions.