A common argument against anarcho-capitalism is that, without a state, private property can not be protected and the workers in companies will collectivise and take ownership. The common rebuttal to this is that capitalists will hire private defence agencies (PDA's) to protect their property. This may be true, but one potentially significant flaw to this rebuttal is that the private defence agency workers themselves may seek to gain control of the PDA. What protects the protectors? Once the workers begin seizing the company it's unlikely the capitalist will be able to help himself and it's very unlikely that a competing PDA will come to their aid. The anarcho-capitalist world may have many sole proprietor and partnership institutions as they do now, but it seems likely to me that they would be protected by PDA's that are cooperatives. What do you think?