Well, our pity for the victims should certainly be equal in all cases, but it is perfectly rational to be more interested in and more worried by the terrorist who kills for Allah than the terrorist who kills for Jehovah, for Buddha, or for some other reason. Firstly, Allah's followers produce far more murderers proportionately than the latter groups. Secondly, the former group is a world-wide network, which I don't mean (necessarily) in the formal organisational sense, but in the sense that the ideology causes which drive Islamic terrorism are a universal phenomenon found wherever there is a large Muslim population. Thirdly, the nasties who torch a black church are home-grown nasties and we're stuck with them, but the nasties who do it for Allah are (in the case of Europe - the Balkans aside- and North America ) in those places by invitation or by deliberate government policy.
I'm sure some people in Edmonton at this moment will be asking themselves whether Canada might have been better off without one more Somalian refugee. Naturally, for legal reasons, they won't be saying it out loud.