The koran has quite a few passages that are, well, violent and quite horrific towards non-believers.
Luckly moderate and the majority of Muslims today view them as "things of the past" and relic passages of a time long gone.
But not ALL muslims view them as such.
Just like not all Christians view passages about "love they enemy and pray for who persecutes you" and "judge not", as passages that superceed OT passages that SEEM to advocate violence and such.
Psalms 144:1
Praise be my Lord my Rock,
He trains my hands for war, my fingers for battle !