Why not? What makes land on a planet/moon/asteroid/whatever so fundamentally different than land on the celestial object we currently inhabit that warrants complete rejection of current systems of property rights? Imagine if your government decided that land should not belong to anyone, that it was the property of all mankind, and therefore would not recognize any claim of ownership by any person, corporatation, or goverernment? Property would still be owned in the sense that if you came to my house with enough firepower you could effectively own my house and I would have no way to reclaim it without bringing in even more firepower. Property rights are a cornerstone of civil society, and I see no reason why in the future when issues of land ownership beyond Earth become non-hypothetical people will demand more than impractical "for all mankind" property law.

Will we carry warfare with us into space? Probably. Along with creativity, hope, art, love, stupidity, science, religion, crime, and basically everything that represents what humanity is. There's no point getting upset about it or expecting that there should be some kind of Star Trek utopian society in space simply because it's "space." You have to work with the Homo sapiens you have, not the Homo sapiens you wish you had.

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My first space mission!

Nicely said, hypersonic. Many a utopia has fallen because it was run by idealists who didn't wake up and smell reality. The universe cannot be run on nobility alone.

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Freedom For Fission A breath of fresh Iodine-131

I don´t think there´ll be much room for stupidity in space. Deploying ordnance in space seems very costly to me. I really don´t think there´s a practical way to take warfare into space.

Adding: I believe space colonization will demand unprecedented colaboration; it ill require mankind to behave differently.

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There’s probably no God. Now stop worrying and enjoy your life.

On the contrary, deploying ordinance in space is much easier than moving the large numbers of people around that is required for colonization. The velocities involved in space travel make just about anything a weapon. Also, colonies on any body in the solar system would be vulnerable to nuclear warheads launched from any other body, with the same technology we currently use to send rovers to Mars and probes to Jupiter and Titan. These aspects of our behavior will not go away when we leave the Earth. Humans are humans, and we will always find clever ways of overcoming obstacles, for good or bad.

There's already stupidity in space, remember the Mars Climate Orbiter? Or read the book Dragonfly by Bryan Burrough for some good examples of human spaceflight stupidity.

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My first space mission!