And onto the issue of the topic...
I must say there really is NOTHING that says we are right or wrong. Every person believes a different thing, and every person acts differently.
If person one believes that Tacos are delicious.
Then person two thinks they are disgusting, and prefers Burritos, it doesn't necessarily mean his opinion is any more right then person number one.
But why do we THINK we are right? Because it's in human nature. Religions and Nations alike all think they are right, and all think that "Good" is on their side.
In World War 2, we believed we had the side of good and God on our side (or some supreme being), and that we would prevail over the evil. In Germany, the Nazis believed they were on the side of good and were doing Gods will. Were they right or wrong? In my belief, the Nazis were the bad guys. But that doesn't neccessarily mean I am right.
There's a counter to every arguement.
Nothing is ever black and white, the world is Grey. This discussion is more of a philisophical question than a political question, and honestly I'm no Philisoph, so I couldn't answer the question any better than anyone else can.
(Excuse me if I typod... It'd Midnight and I'm tired.)