Marilynne Robinson said this quote

The parents of these young soldiers would come to me and ask how the Lord could allow such a thing. I felt like asking them what the Lord would have to do to tell us He didn't allow something. But instead I would comfort them by saying we would never know what their young men had been spared. Most of them took me to mean they were spare the trenches and the mustard gas, but what I really meant was that they were spared the act of killing.