You are mistaken if you think soldiers during WWI and WWII didn't act like that. When they got shot, do you think they shouted "Oh, golly!". They were there to KILL other people. And they were away from women for MONTHS at a time. Soldiers didn't just start swearing during Vietnam - Vietnam was just the first war fought on TV. The films they made to drum up support for WWII wouldn't have been as effective if they put in phrases such as "we shelled those nips right in a**", as I heard from my former next door neighbor, a WWII amry veteran)