I suppose there are two things that are required for a free world. One of those things is anarcho-capitalism, however this by itself is not sufficient. That is to say that anarcho-capitalism is required for total freedom but does not ensure it. In order to obtain total freedom, we additionally require that militant libertarianism dominates the world. Anarcho-capitalism is an economic system, and it is the only economic system that is compatible with freedom. However, it is possible to have a world full of slaves even if anarcho-capitalism is the only economic system utilized. Private police forces could enforce laws that say black people are slaves, for example. Clearly this world would not be free, however it would still be anarcho-capitalistic. First I will explain why anarcho-capitalism is the only economic system that is possibly compatible with freedom. In an anarcho-capitalist economic system, there is no taxation. Taxation is inherently theft. It is the violent redistribution of wealth, most commonly managed by a centralized government force. Under non anarcho-capitalist economic systems, people put forth effort to obtain wealth only to have large percentages of the wealth taken from them at gun point. Of course, the armed thugs who steal the money from the wealth producers use the stolen money to fund themselves. Thus they are very parasitic. In order to maintain the power to be parasitic, they also distribute the stolen wealth to some of the common people, in order to gain the support of enough people that they can continue being parasites. In the current economic systems utilized by the governments of most of the world, people are not given a choice in regards to many of the services they obtain. People are currently forced to fund organizations that they are against (ie: the DEA), they are also largely forced to fund select service providers (ie: police, fire, roads, schools, FDA, etc), in some cases they are allowed to use alternative providers but they still must fund the state selected providers, in other cases they are only allowed to use the providers selected by the state. This is state control of the market, it reduces peoples ability to spend their funds on the things they desire, it reduces the amount of capital that people have available for themselves, it forces people to fund things they are against and it is based entirely on violence, collectivism and slavery. This sort of market is against the better interests of all the people, especially the most productive people in society. This sort of system is also ripe for corruption; the politicians can get funding for programs such as the war on drugs because everybody is forced to fund these programs even if they are against them, the politicians always give contracts to their friends and financial supporters, indeed entire industries rise up that serve the political elite. Wars are fought and millions of people are murdered simply so friends of politicians can get money in military contracts, we ourselves are enslaved so the prison industrial complex can continue profiting off of our slavery, etc. In addition to this, we are given sub adequate services, we are forced to pay for things such as roads and schools and yet the quality of the provided services is much below the cost we are forced to pay for them. The lack of competition also stifles innovation, etc. The list of reasons why the current economic system is horrible and totally counter to freedom goes on and on, but at a fundamental level it is counter to freedom because it is built on the backs of financial slaves and because it restricts our choices and forces us to fund our oppressors. Now of course simply having a totally free economy is not going to guarantee that we have freedom. A free economy could lead to private parties paying for slave traders to enslave us, paying for armies of robbers to steal from us, etc. Even though a totally free economy is required for total freedom, it is not in itself sufficient. This is why we must also have militant libertarianism, of course voluntarily funded. We need police forces that enforce libertarian laws. That means if somebody hires a private police force to arrest drug dealers and steal their drugs and money, the libertarian police force will treat them as robbers and kidnappers. Only when the militant libertarian forces are capable of overcoming all adversaries, can we hope for actual freedom. So no, anarcho-capitalism by itself is not sufficient for freedom, however it is indeed required for it. However, only when militant libertarianism dominates the world, protecting the anarcho-capitalist economic system as well as our human rights, can we hope to obtain freedom.