I didn’t see the publication date listed, but from comments in the article it must have been written between the fall of France and the establishment of Vichy France, and the attack on Pearl Harbor. So between July 1940 and November 1941. I would guess late 1940 before the inevitability of conflict with Germany had become apparent?
Silly me, now I see you posted it in the OP. August 1941. So much for pinpoint accuracy, but at least I was over the target!