Power vacuums are not left unfilled for long.
Also, I've never met a "true" (in the sense that they tell you about it as soon as you talk to them) libertarian who isn't also a raging asshole.
But there are assholes on all points of the spectrum, so I'm not sure what that proves. :D
It's an incentive for other actors to try to imitate the role of government through other means.
Actually, not just Somalia - Africa is ripe with examples of these.