I've also seen real-world governments ruin their own economies by making short-sighted (or just plain stupid) decisions. And I've seen Ponzi schemes in a lot of government plans as well.
What it comes down to is this: is the general populace comfortable enough to engage in open economic activity?
You can see that there is a lot less confidence in the US and the rest of the world, in large part due to various stupid decisions. But this doesn't prove that anarcho-capitalism works. It just shows that corrupt capitalism doesn't work well either.