“...my son, currently serving with the Marines, has told me that a Celtic cross tattoo will result in his separation from the service. Lots of heritage symbols have been declared hateful.”
May I take the liberty of rephrasing your thought with the info I am gleaning from this post. “All WASP heritage symbols have been declared hateful”?
They aren't even black Anglo-Saxons.
Or even Anglo-Saxons of any color.
These are subtle distinctions that make no difference with the folks who believe first in "good order" and secondly in "individual preferences".