The people in charge of enforcement would become a de facto government. What distinguishes a government from any other organization is the monopoly on violence (more precisely, the monopoly on deciding when and how violent measures can be employed), and enforcing property rights sometimes requires violence (e.g. if someone refuses to leave your home, eventually the police will have to physically remove them against their will).
Blockchains do nothing at all to help anything about this situation. You could use a blockchain to manage ownership, but it would be far more efficient to use a central database of some kind that is held by whatever organization is responsible for enforcing property rights. In the end you are not going to care how your ownership is managed, you are only going to care that, if someone tries to violate your rights, the police will come and protect you. You need to trust that the enforcement will actually be applied, but what difference does it make if you use a blockchain?
In a decentralized society, there may be multiple organizations deciding on when and how violent measures can be employed — and they could be as small as one person. If each organization thinks a different person is the owner of a property, that would be very unstable. However, if they all agree that a certain blockchain implementation of deeds is what decides ownership, then they can co-exist more peacefully. Not saying there aren't other hurdles, but that is certainly one of the big ones.
That does require that most of the society agrees on some set of principles, but that's true of a centralized government too: most of the society has to agree they are legitimate. Going back to the decentralized society, everyone would agree that the blockchain determines ownership and currency. So, an organization that accept those is viewed as legitimate, one that doesn't is illegitimate. In that scenario, illegitimate organizations would be less stable than legitimate ones.
So, the existence of a system that allows people to all agree in things like currency and ownership without giving that power to one specific organization is a step forward into making decentralized societies possible. Is it sufficient? Most likely not.
It is indeed not. I'm not claiming that all problems are solved and that decentralized governments are easy or even possible. Just that blockchains solves some of the problems in that area.
> In a decentralized society, there may be multiple organizations deciding on when and how violent measures can be employed [...] a system that allows people to all agree in things like currency and ownership without giving that power to one specific organization
What, did you read Snow Crash as u- in stead of dystopian? What's to say they'll all agree?!?
The important point is what happens when two of those organisations disagree. What happens when I have Mr Chen's Robot Dog Republic saying I own a property -- because they have the blockchain to prove it -- and evicting you on my behalf, while you have the Cosa Nostra Pizza Delivery Co. saying you own it -- because they have the blockchain to prove that -- and evicting me on your behalf?
Civil war, that's what happens.
Decentralising stuff that everyone needs to agree on sucks.
You cannot get your hacked bitcoins back even if you are the government with police and army. Lots of things that government does can be replaced with a smart contract. Hey, you can even have direct democracy - vote with your citizen token for a change in a smart contract and voala the law changed and immediately enforced.
It could be the norm. It all depends on how the society is organized. If there is a system of law and a court and you prove someone stole something from you, the government will coerce that person to give you back or pay some sort of fine. For instance, even if the system says you own those bitcoins, a court can rule that you give it back to the person you hacked and also pay for the costs of the case. The same goes for smart contracts. A court may rule that the contract is invalid and require one of the parties to pay the other, regardless of the smart contract. So, that technology doesn't, in and on itself, revolutionize any of that. However, it could be made into law that a court cannot revert a smart contract or that the contents of a digital wallet belongs to whoever has it, regardless of how it was obtained.
Blockchains do nothing at all to help anything about this situation. You could use a blockchain to manage ownership, but it would be far more efficient to use a central database of some kind that is held by whatever organization is responsible for enforcing property rights. In the end you are not going to care how your ownership is managed, you are only going to care that, if someone tries to violate your rights, the police will come and protect you. You need to trust that the enforcement will actually be applied, but what difference does it make if you use a blockchain?