Anarchy has nothing to do with “not having government” you fundamentally misunderstand anarchism if you think that’s what it means. Somalia in no way resembles what any anarchist philosophers said. If you think it does, I must know, which philosophers are you citing?
If you want a real-world example check the zapatistas, or the native americans pre-colonialism.
If you say “why didn’t they win against white people if their ideology was so good” and the answer to that is rather obvious, exploiting people is very efficient.
As for what would be different, it is very difficult for a nation to fight the world, it’d be easy if that nation was the US.