In the Roman Republic, they had a principle of never bringing armed troops into Rome. Until someone brought armed troops into Rome. Then people started bringing armed troops into Rome.

In Libertarian New Rome, they had a principle of never initiating aggression. Until someone initiated aggression. Then people started initiating aggression.

Principles don't take actions off the table, and so long as an action can be applied to the actors direct benefit, there's always the possibility it'll be used.

And violence has a rich history of being incredibly beneficial to the last guy standing.

So it's naive to believe a society of people would follow the NA principle, especially when the world is so full of powerful actors that initiate violence all the time.