Why do Americans act and think like they're always right, & others are always wrong?

Americans love having an enemy. Before it was communism, today it's Muslims. Americans think they have the right to unlimited hurtful freedom of speech, whether it incites or instigates the other group that it's targeted at. For eg: it's very common for Americans to call their Prophet a pedophile, or a terrorist etc. This is hurtful, instigating speech. I have never seen a Muslim call Jesus or Moses such things. I've never seen Muslims say all Christians are terrorists because Hitler killed over 6 million Jews, & that the US killed over 2 million Iraqis. I've never seen Muslims say all atheists are bad because Stalin committed the most brutal macres of all times. So I think it's time to get past petty fights, & work together to build better understanding.