My feeling after watching Avatar

There is a unique mine in Pandora planet called “Unobtanum”, which is the reason why human discovered this planet. People have been sent to this planet by some colon technique which allowed him to talk to the native people, Na'vi. The main character is Jack, who is an injured marine. He met the Na'vi princess when he just arrived, and the princess taught him a lot about this planet. Gradually, he emerged a harmonious thought that the human should not mine this planet anymore. When the human began to invade this planet because of the mine profit, Jack thought he could resolve this interest conflict by persuading the leader of Na'vi to leave the Hometree, which is a tree the Na'vi people have faith in. Jack has been lock by Na'vi leaders and soon after, the Hometree has been destroyed by the human, the leaders died in the bombardment. Because of jack betrayed the company, jack has been captured and locked again. But he escaped and inspired the Na'vi people to fight back. Finally the Na'vi won and jack became the leader of Na'vi.
The first thing occurred to my mind when I finish Avatar is how resentful the imperialism is. Crusade supposed to be vanished centuries ago, and now, people are invading other planets for useful resources. People are selfish and utilitism, they would do any harmful things to get the profit no matter how much damage they could cause. Humanity in nowadays are based on the no conflict of interest, people should regain humanity and build a brand new society.