ABM Deployment Vis à Vis China: Canada Reacts to Sentinel (June-December 1967)

On September 18, 1967, U.S. Secretary of Defense Robert McNamara announced the American decision to deploy a “light” ABM system to deal with an emerging Chinese nuclear threat. The documents in collection highlight how Canadians prepared for and grappled with this decision. The announcement itself was cause for concern, and Canadian officials articulated that they would not participate in a North American ABM system based on current circumstances.

Although Canadian officials expressed a degree of apprehension regarding the potential Chinese response to ABM deployment, they also continued to focus on obtaining information on the status of U.S.-Soviet arms control talks – likely in an effort to confirm no further ABM deployment in the near future. Additionally, they continued to maintain interest in the implications of ABM deployment on the broader issue of arms control, and the non-proliferation treaty.

While the Canadians continued to seek concrete information, they themselves took a vague stance on their participation in a North American ABM system. While Prime Minister Pearson had confirmed a policy of non-participation by December of 1967, a memorandum from the same month suggests he had not completely shut the door on future involvement.