Muslims are killing each other every day so giving the finger is not that big a deal.
It doesn't matter to me whether he is Muslim or not but what I find amusing are those who go to pains to say there is no connection to this guy and Islam. So what either way? If he is a Muslim does that mean all Muslims chop off people's heads? If he isn't a Muslim does that mean that no Muslims chop off people's heads? Some do, most don't, would seem the honest answer but right now, as well is a few years ago, it does seem de rigueur for some members of the R of P. to make a point of decapitating innocent people.
Whenever there are stories abut pizza shops being bombed, or buses exploding, many rush to say 'there is no evidence this had anything to do with Muslims' and then, shortly thereafter, it turns out that Muslims, almost inevitably, were involved. And after these random killings no one rushes to say they weren't Christians, Jews, or atheists. It's now become reflexive, because of the numbers, that we assume it is some Muslim.
But why not guess, given the odds, that it is probably a Muslim who did the beheading? Are we concerned about hurting their feelings? Are they not adults, or so backward they need constant patronizing? Christians can take these attacks on their religion, Jews certainly can, but Muslims seem to need special care and handling. Why is that? Are relations between religions expected to improve if we stay silent??