Your quote:
"But isn't the greatest crime against humanity the outright distrust of anyone different?"

No, that is not a crime against humanity that is stupid. But if the distrust is as a result of historical experience dealing with people socialized in a particular way then it is wise to distrust then seek confirmation one way or the other. It would be wrong to take action based on distrust. Even if all this is not considered I fall to see how this could be classed as the greatest crime against humanity.

For me the greatest crime against humanity is taking the life of another outside of proof of a direct threat on ones life.

Your quote:
"It doesn't matter where a person learns skills or obtains things, if they commit crimes which intentions to do damage to another human being, that is their fault alone. No one makes another person harm another."

Unfortunately that is not the position Bush takes on behalf of Americans. He stated that those who finance or harbor terrorists are as guilty as the terrorists.
I agree with him on this. In the same way those who finance and elect governments to act on their behalf must accept responsibility for the wrongs committed by their government. There are personal responsibilities and collective responsibilities. Both are correct.