David,
you keep harping on about Christianity having modernised. I beg to differ, because I cannot reconcile your statement with the atrocities committed in Bosnia and other places in ex-Yugoslavia. How modern were those Christians shelling the busy marketplace? Was that not terrorism, aimed at non-combatants as it were? And that is just one of the examples that the 1990s provided us with, in that small corner of the world alone.

No, I'll go with CarolC - extremism is the problem. And racism is not "caused" by religion, it's caused by perceived differences: of skin colour, tribal allegiance, anything that makes one uneducated moron fear another. Religion is then sometimes used as a convenient cloak to dress up racism and to facilitate conversion of others to the "cause" of the racist. And the racist will use any interpretation of the Qur'an or the Talmud or the Bible etc that suits his/her purpose. He/she is helped (unwittingly or not) in this by those who - as dianavan points out - take the old scriptures literally, making no allowances for the intervening passage of time.

But I disagree, dianavan, that religion is redundant and listening to one's heart is sufficient. One could say that this rule is followed by killers, thieves, mass murderes etc. Not all hearts are pure, unfortunately, so some "external" code of conduct is still required.