I don't think my dad enjoyed the Phillipines (WWII), Korea or Vietnam, for various reaons. All different. While he didn't actually fight in Korea, he served there (cold!). There aren't many like him left.
No, not many. When last I heard only about 13,000 surviving vets of those three wars.
The most prized gift I ever got him was a cap that says “Veteran WWII-Korea-Vietnam”.
It is a real door and conversation opener. He loves it.