People become more religious and stay religious when they face more dangers in war

The old saying that "There are no atheists in foxholes" seems to be true.  Being in the military during war causes people to be more religious and to stay that way and the effect is occurs for who had the most difficult experiences.  From Science20:

. . . But does war really transform people, or does it simply make the fleetingly religious more so for a short time? A recent analysis of archived surveys of Army Infantry soldiers after a battle -  Samuel Stouffer's "The American Soldier" World War II  research (1) - found self-reported reliance on prayer rose from 42% to 72% as that battle got more intense.

"The question is whether that reliance on faith lasts over time," said Craig Wansink, author and Professor of Religion at Virginia Wesleyan College, who did the analysis and co-wrote the paper with his brother Brian Wansink, food marketing expert and Professor of Applied Economics and Management at Cornell University. The World War II generation is a good one for analysis because the interest was religiosity long-term and young people in the 1940s were more religious overall than more recent generations.

A second analysis of survey results from 1,123 World War II veterans showed that 50 or more years after combat, most soldiers still exhibited religious behavior, though it varied by their war experience. Those facing heavy combat (versus no combat) attended church 21% more often if they claimed their war experience was negative, but those who claimed their experience was positive attended 26% less often.  . . .