What really defeated Napoleon during his invasion of Russia? Lice borne disease, which is not nearly as glorious as epic cavalry charges or thundering cannons.
Left unanswered - why wasn't this an equally grave problem for the Russians?
ERRATA: Clearly we need the famous Minard graphic, and a bit of commentary:
This was a battle of logistics as well as of tactics; the French Army lost more men to starvation, desertion, typhus, and suicide than to combat. The Army advanced faster than supply trains could manage, and there was no forage available.
Suicide? Seems redundant with all the other opportunities for an early exit.