The Overlord wrote:
The Son'a gave up their right to live there by trying to take over.
Why? Maybe the Son'a had a legitimate point, that doing hours of needless back breaking labor to serve some Luddite philosophy is just pointless and counter productive.
The Ba'ku used force to expell the Son'a from that world and now the Son'a are using force to do remove the Ba'ku. Turn about is fair play.
The thing is with this argument, is your confusing an exile with a theft.
The Son'a knew the rules of the society in which they lived. If you note the dialog, you'll see that it was an attempted coup, somewhat different to a legitimate opposition or difference of viewpoint.
When there is an argument, at some point, one side wins.
In the end, the parents set the rules of the house.
Please, the only difference between a coup and a revolution is who is the winner and who is the loser.
The American colonists revolted against their British colonial system, no one seems to treat that as some sort of illegal act.
Again, maybe the Son'a had good reason to revolt, maybe they felt that a society that created hours of meaninglessness back breaking labor that could be done away with some technology or that a policy of isolation was counter productive.
The Son'a are just doing to the Ba'ku, what the Ba'ku did to them.
Heck, how did the Ba'ku even beat the Son'a if they are pacifists? The whole relationship between the Ba'ku and the Son'a makes no sense.