YOu must be playing a different game then, because in none of my games, save RTI and where I was involved in getting the Natives to go to war with other factions by being an ally on either end, they never declared war on the other Euro nations holding colonies there (or the colonies themselves).
The only time there was some sort of war was Spain deciding to attack the Pueblo and then the Cherokee, but the Indians themselves never declared war. They do against the human player though.
Add to that, CA announced in the most recent patch that emerging factions are only at war with the human, not with AI, which suggests that really, its a human vs AI game rather than a free for all.
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