If Simon and company were interested in producing supplement books, that would be an interesting place to start.
Warhammer Fantasy (of all things) did something really close to what I think you’re describing, Dennis. In one edition of the rule book, all of the special missions were presented as “historical” battles from the setting, taking a page and a half to describe the canon battle and how to replay it, then having about a half-page or so describing how to run it as a generalized scenario between any two factions.
Presumably a dedicated scenario book on real-world events would spend a great deal more than a page or so describing the real history behind the scenario, which could provide a really useful jumping-on point for new players— especially when it comes to armies that are less well-known in the popular consciousness.
(Take all of the above with due skepticism— I am neither a publisher nor a market researcher.

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