This work is a path-breaking study of the changing attitudes of Canada, Australia, New Zealand and South Africa to Britain and the Commonwealth in the 1940s and the effect of those changes on their individual and collective standing in international affairs. The focus is imperial preference, the largest discriminatory tariff system in the world and a potent symbol of Commonwealth unity. It is based on archival research in Britain, Canada, Australia, New Zealand and the United States.

This book explains the causes and consequences of the intersection of two transformative global forces - trade and conflict - since 1500. The nine historical case studies - interspersed over 500 years and spanning the globe - make a major historical contribution to the enduring debate about whether trade makes peace more likely.