I own a little piece of the planet for as long as I am alive, and it is socially acceptable for me to kill anyone who comes on said land against my will.
What if the government authorities ask you to vacate your land, with or without adequate compensation? My family lost almost 600 acres of land six decades ago, when the local communist government implemented the land reforms act. They took land from the big land-holders and distributed it to the landless peasants. And we received no compensation for the land we lost. What can we do? If we go to the court, the legal battle will wage on for many decades and the chances are that we will never win it.
Then I kill those who come on my land, until they kill me. :/
Not much I can do when an organized group decides they want what I own.
P.S. THANK YOU for contributing to the discussion instead of just reading the first post and commenting.