A friendly linguistic note about the plausibility of a typical military expression.
1° In French, "Bruno" is a first name. In Indochina, the captain (since 1945) then commander (from 1950 to 1953) Marcel BIGEARD (1916-2010) had actually taken it as a radio callsign ("Bruno" = "B" as "Bigeard"). The charisma of the character quickly made it a nickname, immediately transformed into a living legend by the troupe.
2° In the same way, if "Mon" is known as a personal pronoun, since the Renaissance this short and clear word is among French-speaking soldiers the equivalent of "Monsieur", that is to say of "Mon Sieur". The word "Sieur" (from the Latin senior) is today an old term but it corresponds perfectly to the Anglo-Saxon "Sir".
"Mon Capitaine" must therefore be understood as "Mr. Captain". English is more direct and straightforward!
3° This is why the particular expression "My Bruno" - as in the introduction to the excellent scenarios of Diên Biên Phu by David GALSTER(**) - could never be used by his superiors or his subordinates because it was too familiar, rather comical and even equivocal.
So how do you designate "Lt. N-X-T", "Maj. MB" or "Col. dC" in-game? Best to keep it simple!
A choice:
- "Mon" followed by the rank in French or, in the specific case of DBP scenarios, "Bruno, your mission is..." (without "Mon");
- The equivalent rank in English, alone;
- "Sir".
Subsidiary question:
Historical names being abbreviated, is it for a specific reason (a text of law) or out of caution as to the rights holders, or even political correctness?
I happen to have a similar problem elsewhere (a custom scenario to be uploaded) with portraits of contemporary historical figures, all deceased (a Public Domain issue).
LN59 [:D]

(*) Note that this could very well have been the title of an Edith PIAF song.
You know, this female singer that we hear on a gramophone shortly before the battle of Ramelle in "Saving Private Ryan".
A great Lady of the music hall made internationally famous thanks to her songs "Mon Légionnaire" and "Je ne regrette rien"...
(**) My warmest thanks to David GALSTER of the CS Legion for the historical nuggets he offers us with the Diên Biên Phu scenarios;
for his booklets (PDF) too that can be found in the 'Additional Resources / CSLegion Vietnam War Blog Posts' directory of the game.
"Quel beau travail il a réalisé !" [&o] What a great job he has done!

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