What does the Canadian Constitution have to say (or not say) about Canada's recent war in Afghanistan? The question seems intellectually natural, but has seldom been asked – not least because in Canada, the fields of constitutional law and foreign affairs, in both scholarship and praxis, are often near-perfect strangers. The seldom examined second recital of the preamble to the Constitution Act, 1867 (once the British North America Act, 1867, and hereafter the ‘1867 Act'), reads that the “Union would conduce to the Welfare of the Provinces and promote the Interests of the British Empire.” The only provision of the 1867 Act that explicitly references foreign affairs is section 132, although it speaks to the implementation by Canada (legislative and executive branches) of imperial or British Empire treaty obligations. One can therefore propose with reasonable certainty that both the character and paucity of explicit language on strategy in the text of the founding legal document of the modern Canadian state betray a fundamental reality: that Canada, constitutionally speaking, was never intended or expected to be a power player of any note in the world, but, rather, was constituted as a strategic appendage or auxiliary kingdom of the British Empire— its instruments and interests subsumed to the strategic designs and direction of Westminster.