World peace will never be achieved. Due to one simple reason...
GREED It is the root of all evil.
I think it is pretty obvious that the war in Iraq was fought for oil. Afghanistan was just a stepping stone, too bad Osama gave the US a reason to do so. Why is is that with so much disagreement over the usage of nuclear power in North Korea and we still don't see a single US marine on their soil? Put it bluntly, NK is a hilly and barren land with no resources whatsoever.
As for the rest of the bombings around the world, those are just "tit for tat" actions.
So who started the war? The terrorists or the rest of the world? Going into war is akin to waking a sleeping tiger to get his reproductive organ for our personal usage.... what do you think the tiger would do?
