[Demidog]

Nations and states don't "claim" property,

But they do claim territory. In my 81 I explained the distinction between the sovereignty of a nation and the sovereignty of the individual and how they might differently interpret their rights to certain property.

The territory of a sovereign nation is made up of the lines of demarcation beyond which their laws cease to carry any authority.

That territory is in fact claimed however. And it is within their power to defend and protect those borders. Anyone who sets foot within that territory does so with the explicit knowledge that he is subject to all laws in that territory.

Any claim he makes on property within that territory is null and void if he hasn't purchased or negotiated rights to that property from either the individual who currently holds rights to that property or the nation which holds claim to the terrority.

Anything outside those actions is legitimately considered to be criminal trespass and theft.

[annalex]

The system you describe is state ownership of all unclaimed land; when a citizen claims previously unclaimed by another citizen land, he in fact receives it from the government. This puts the government in the role of the originator of all real property. Historically, such systems of property exist as a result of a war for territory that a government has fought; the land in the American West was partly distributed to homesteaders in that fashion, and partly remained government property. This is not the only system of real property, and it has no justification other than in historical circumstance; the natural law, and the libertarian principles would place the government in its only proper role as law enforcer and not a landlord-by-default.