4 April 1946: Memorandum for Mr. Robertson

In this memorandum for Norman Robertson (the Under-Secretary of State for External Affairs) G.G. Crean (also of the Department of External Affairs) lays out the arguments for transferring HYDRA from British authorities to the Canadian government. Crean notes that the HYDRA network could be used to carry External Affairs traffic between Ottawa and London and Ottawa and Washington, and it could also be used to carry signals intelligence traffic (including raw intercepts) between Ottawa, London and Washington. Perhaps most crucially, Crean notes that a Canadian takeover of HYDRA would "contribut[e] substantially to the post-war signal intelligence effort of the Commonwealth and the U.S.A." This contribution, he argues, could ensure allied assistance in Canada's own cryptographic efforts, as well as "ultra intelligence" from both the United States and United Kingdom. HYDRA, then, was a way in. It was Canada’s key to participating and reaping the benefits of signals intelligence sharing agreements, and to enhancing its own intelligence capabilities.