A 19-year-old – the youngest cohort listed – would be 33, maybe the end of the peak period to start serial killing – 14 years after 1944. That’s in 1958, and that’d have been the tail end of American WW2 veterans being in the prime serial killer initiation age. The boom had started then, but the highest rate of increase came later…and that’s looking at the very tail end of the WW2 vets.
The serial killers would mostly have been children or young teens during World War II, not actually served in it.