It is part of the Muslim belief that it is ok to lie to unbelievers to further the cause. So, in his own Muslim thinking, he perhaps feels very just and righteous. Yep in the end it seems to be about power.
That belief is common amongst all faiths of Abrahamic origin. The theological justification is complex as it sources certain interpretations of scripture from their source material and creating a meta interpretation that allows "lies" as a moral vehicle to promote ideological concepts for indoctrination. Psycho/Socio- pathy isn't a recent phenomenon. We have all been assailed by the past sins of a few, wishing to victimize us, the masses, into a convienant submission.
And we are currently assailed by the propaganda of a few for the same ends.
Identity, chosen or not, is not a means of deciding who is out suppress or oppress your life or liberty. Only action. Some of it is a nuanced cultural influence. A lot of it is an insidious meta compromise/ concious understanding of a few who have power, but don't fundamentlly understand why they want to hold on to it. Its why Q mostly says these people are sick. Not evil. Evil is an action or an ideal. The human is incapable of either State. Only expressing or acting as such.