That's why anarcho-libertarians are as uselessly utopian as any socialist. Thomas Hobbes was right.
The principals of anarcho-libertarianism are correct and are the best solution for prosperity. However, the practice of anarcho-libertarianism is not possible without all other variables being highly controlled. Anarcho-libertarianism by itself would devolve into chaos and bloodshed almost immediately.
This is why maybe a Monarchy to highly control the variables (foreign relations, warlords, crime, immigration, virtues, culture, religion, etc...) and strictly enforce the non-aggression principal internally among the subject maybe the closest a society could get to anarcho-libertarianism and the greatest possible prosperity.