After undertaking some very preliminary research on the subject, I've found one significant pro-union period work:
Union Now: A Proposal for a Federal Union of the Democracies of the North Atlantic by Clarence K. Streit (
available online). It had the misfortunate of being first published in 1939 and was therefore mostly ignored during World War II, but Streit's work gained surprising currency post-war.
Attached is Streit's map of his envisioned world (using ~1939 borders). He also presents a sample constitution for his North Atlantic Union (see Annex 1).
Are there any thoughts on the plausibility of his proposal?
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