Yeah it's interesting how they can get away with that, if you read that article the guy's saying he would go and kill everyone in canberra, and saying that a war in australia between islam and the rest is inevitable - shows how narrow minded they can be.
From a biblical perspective the religion islam was birthed from Ishmael, who was the son conceived from Abraham and Hagar - who was in a way a surrogate mother for Abrahams son because he believed that his wife Sarah could not longer have children (she did, hence the rest of the genealogy but that's beside the point), It was Abraham taking matters into his own hands rather than depending on God for the promise he gave him (you will have son,etc).
He grew up to be a man of the desert wilderness, with a wild and hostile attitude toward people, exactly as God described him to his mother before he was born.
"Behold, you are with child, and shall bear a son; you shall call his name Ishmael; because The Lord has given heed to your affliction. He shall be a wild ass of a man, his hand against every man and every man's hand against him; and he shall dwell over against all his kinsmen." (Genesis 16:11-12 RSV).
Just some food for thought anyways, it is interesting how closely the modern muslim/arab nations resemble those verses.