So -- which side is right? Is Islam essentially violent and intolerant or essentially peaceful and pluralistic? Do the guys with the bloody machetes represent Islam, or are they an aberration? I think that anyone who tries to answer this question simply is doing so deliberately in order to score political points.
Objectively, there's no denying that today Islamic extremism poses more of a threat than other types of religious fanaticism. There are complex historical, social, and cultural reasons for this. But this is not a matter of the text of the Qur'an being inherently more susceptible to intolerant interpretations than the Bible.