Hitchens says somewhere that he didn't suffer from cognitive dissonance of the sort that arises when a deeply internalized religious upbringing collides with the contrary values of the world, since he never took religion or theism seriously in the first place. But then I say religion was never a Jamesian live option for him. But if not a live existential option, one that engages the whole man and not just his intellect, then not an option explored with the openness and sympathy and humility requisite for understanding.
So why should we take seriously what Hitchens says about religion? He hasn't sympathetically entered into the subject. He hasn't fulfilled the prerequisites for understanding. One such prerequisite is openness to the pain of cognitive dissonance as suffered when the doctrines, precepts and practices of a religion taken seriously come into conflict with a world that mocks them when not ignoring them. But in Hitchens by his own account there was not even the possibility of cognitive dissonance.
Consider two working class individuals. The first is a sensitive poet with real poetic ability. His family, however, considers poetry effete and epicene and nothing that a real man could or should take seriously. The second is a lout with no appreciation of poetry whatsoever. The first suffers cognitive dissonance as his ideal world of poetic imagination collides with the grubby work-a-day-world of his unlettered parents and relatives. The second fellow obviously suffers from no comparable cognitive dissonance: he never took poetry seriously in the first place.
The second fellow, however, is full of himself and his opinions and does not hesitate to hold forth in the manner of the bar room bullshitter on any and all topics, including poetry. Should we credit his opinions about poetry? Of course not: he has never engaged with it by practice or careful reading or the consultation of works of literary criticism. He knows not whereof he speaks. His nescience reflects his lack of the poetic 'organ.'
Similarly, a fellow like Hitchens, as clever as he is, lacks the religious 'organ.' So religion is closed off from him and what he says about it , though interesting, need not be taken all that seriously, or is to be taken seriously only in a negative way in the manner of the pathologist in his study of pathogens.
Companion post: David Lewis on Religion