Abstract
Michael Walzer’s use of John Stuart Mill’s A Few Words on Non-Intervention (1859) helped
to inaugurate it as a canonical text of international theory. However, Walzer’s use of the text
was highly selective because he viewed the first half as a historically parochial discussion of
British foreign policy, and his interest in the second was restricted to the passages in which
Mill proposes principles of international morality to govern foreign military interventions to
protect third parties. As a result, theorists tend to see those canonized passages as if through
a glass darkly. Attention to the detail and context of Mill’s first-half critique of Lord
Palmerston’s opposition to the Suez Canal project reveals that his discussion of purely protective
intervention is embedded in a broader exploration of the limits of self-defence,
including the moral permissibility of preventive military force and the use of protective
interventions for defensive purposes. Moreover, reading the text holistically facilitates a refutation
of some objections directed at it by Michael Doyle to the effect that Mill’s conception
of self-defence incorporates elements of aggression which makes it extremely dangerous
when adapted for application to the contemporary world.