Ahh, the great liberal dream of a happy world at peace with cats and dogs sleeping together. Remember this, the human animal is violent. That is why we have climbed to the top of the foodchain on our little rock of a planet. It is this violence that sets us apart.
Wars are always fought over resources. Nothing else. Forget all the nonsense you read in school books about the causes of war and realize in a realpolitik kind of way that war is about the control of resources. Are you aware that the last six wars have been over energy? Don't believe me? Do some research and you will see I am right.
For example, everyone knows we are in Iraq because of the oil. All the reasons we have heard for the invasion are just public relations nonsense. The fact remains that global oil reserves are in steep decline while production steadily increases to meet skyrocketing demand. The US needs oil to continue as a superpower, so we invade Iraq and secure our oil supply for the next 100 years.
And by what right do we claim to control Iraq's oil? Because our troops are all over it and they will kill you if you argue. Like Mao said, all power comes from the barrel of a gun. The US has rewritten the map of the Middle East, has destabilized the global balance of power and has imperiled our national future, all to secure our oil supplies against the rising demand from China and India.
Until we achieve a technological level that frees us from dependence on natural resources we will forever fight one another over the gifts of the earth. Then we'll probably fight over rocks.