I think it was basically a live game of Risk.
Custer was way outnumbered.
The Sioux just whittled them down like a final battle on a Risk board.................
Yes, but the Western Way of War STILL could have prevailed-—however, it takes concentrated fire and unlimited ammo.
This was the same, more or less, situation at Isandlwana, where the Brits overextended their lines and lacked ammo. But at Blood River, some 40 years earlier, Boers with far more primitive weapons, in a laager, defeated a higher ratio of Zulus.
Western firepower is absolutely unbeatable against more primitive foes IF it is concentrated.