Vietnam Era Vet. is a whole lot different than being a Vietnam Vet (Having served there).
You are right, I am a Vietnam era vet, but never served in Vietnam. My tour of duty was Korea.
I understand what you are saying. You have the green and white ribbon.
But current use of the term is:
Vietnam veteran definition
A Vietnam veteran is someone who served in the armed forces of participating countries during the Vietnam War. The term has been used to describe veterans who were in the armed forces of South Vietnam, the United States armed forces, and countries allied to them, whether or not they were stationed in Vietnam during their service.
My NDSM is for service during the VN War. But I do not tell folks I am Vietnam vet, as I consider in country service to be the qualifier.