War's 'Dead Chaps', Literature and Religion

A while ago I caught the end of the second episode of Frank Faulk's documentary on the CBC (link to part one only) about C.S. Lewis and the Inklings. I've now heard the entire thing (I'm nothing if not a procrastinator), and I really recommend it to anyone interested in the kind of influences that have been at work on thought in twentieth century Britain. Despite being an irreligious society with a state church, in contrast to the Americans' religious society with no established church, religion had a lot of influence on British literary culture between the end of the First World War and about the time I was born. Lewis, Evelyn Waugh, Graham Greene and, most importantly in these times, J.R.R. Tolkien all were deeply affected by Christian faith, and mostly a Catholic version of it. But, I think, there is another influence at work here, and that is two of them experienced the First World War immediately, and the other two through a kind of lacuna. Waugh, I think, expressed that lacuna best in Brideshead Revisited (p236 in my decrepit, well-read Penguin Edition):

We went to a number of nightclubs. In two years Mulcaster seemed to have attained his simple ambition of being known and liked in such places. At the last of them he and I were kindled by a great flame of patriotism.
'You and I,' he said, 'were too young to fight in the war. Other chaps fought, millions of them dead. Not us. We'll show them. We'll show the dead chaps we can fight, too.'

For those who survive a war, a common feeling is that they were no better than those who did not, and possibly in some way inferior. But, if Mulcaster's sentiments reflect something Waugh was familiar with, for some of those who just missed a war, there appears to be a nagging sense of inadequacy, a failure to arrive in time that was somehow a personal betrayal of those who died or were killed. In this context, does a quest for meaning lead one to religion?
But, again, there might be even more influences at play. Faulk highlights that Lewis' conversion from atheism to religion had something to do with perceiving a lack of imagination on the part of unbelief, which was somehow related to the emphasis of Enlightenment thought on reason and fact. While we often hear of the terrible crimes perpetrated by believers in Crusades, Inquisitions and Imperialisms, the Enlightenment's responsibility for Racism, Eugenics and the kind of depersonalisation of working people that occurred during the rise of Capitalism are less often commented on. I think blame for each of these can be assigned to reason's antipathy towards 'fancy', a word of various flavours that is extremely useful in this context. 'Fancy' helps us to transform mere numbers of people, or measures of their production, into individuals.
The paradox is that, for the Lewis presented in Faulk's two-part documentary, the actual truth of God's Plan for our Salvation is potentially irrelevant. While we are alive humility and charity ought to make us good people, but after we are dead we won't really matter any more to the survivors, except as an influential memory. And that is exactly the impact of 'the dead chaps' on Boy Mulcaster in Waugh's novel.