My Dad was a bit like that. I could hardly get a word out of him about Yugoslavia. I believe it was to do with a girlfriend he had while he was there, and what he found after they had chased the Ustaše out of her village.
My dad had a story - I think this used to go the rounds and was probably the service equivalent of an 'urban myth' - about a sergeant who stepped up to a young soldier/airman/whatever and said:"Am I 'urtin' you? No? Well I should be - I'm standing' on yer bleedin' 'air! Get it cut!"
'War films' were part of the culture we were brought up with in the 1960s. Most of our dads had been in WW2 (e.g. my dad - RAF corporal sparks in N Africa, Italy & Yugoslavia).Two things our generation used to get from the previous:"A spell of National Service would do you good!""You never lived through a war. We did!"