The thing is that even in an Anarcho-Capitalist economy, things that greatly resemble states will exist. You guys are absolutely correct in saying that there will be private police forces, private armies, etc. Some of these armies and police forces might even enslave people, just like the current governments do! This will effectively make them governments though. This is why we also need powerful militant libertarian forces. The libertarians will also have police forces and militaries, but rather than being funded via taxation they will be funded by voluntary donations and such. Then we will have a market for libertarian police agencies and military forces, and it will very much resemble a state. The only real difference is that we will not be forced to fund any of these agencies, and that we will be able to select between many different agencies in order to make sure we are receiving the best value for our money. This will also cause the agencies to be innovative as they compete with each other. Additionally, it will lower our costs as the agencies will compete with each other financially as well. Of course there will still be networks of criminals trying to steal from us and enslave us. And they can be viewed as states. We simply need to make sure that we are protected from them, and hopefully over time we can eradicate them like the cancers they are. The end goal is to have minimized governments so much that they are small networks forced to hide from the powerful libertarian forces. Essentially we will trade roles with the government; we will live openly and freely and they will hide in the darkness plotting how they will rob us and kidnap us. The difference is nobody will be forced to fund our protectors, but they will do so voluntarily as they desire to remain protected from the government actors.