As mentioned, this trope often applied to Vietnam War PO Ws who found America greatly changed from when they were captured, particularly those who were cpatured earlier in the war, as well as with many war veterans who spent several years away from home.
Some former draft dodgers who went to Canada and were later granted amnesty and returned to the US probably experienced this as well as they too had come back to a country that was different from the one they'd left.
As mentioned, this trope often applied to Vietnam War PO Ws who found America greatly changed from when they were captured, particularly those who were cpatured earlier in the war, as well as with many war veterans who spent several years away from home. Some former draft dodgers who went to Canada and were later granted amnesty and returned to the US probably experienced this as well as they too had come back to a country that was different from the one they'd left.