"Building Bridges" is a very likable metaphor, one of the most vivid, in my opinion, within Cold War, especially Detente rhetoric. Yet the roots of an idea that certain nations are suited to become intermediaries between East and West are older. I can trace aspirations for such a role in my research, concerning WWII governments-in-exile, in 1943, 1944. There I got curious: Who was the first to employ the metaphor in the said context? "Oxford English Dictionary" lists NYT´s W. Safire in 1967 which looks pretty late to me. I also count on possibility that the concept predates the coinage.
Any ideas? Research available?