You know, boys, it wasn’t until the late 70s or mid 80s that you needed a HS diploma to enlist. There were a ton of people who joined or were drafted during Vietnam, Korea, WWII, WWI and earlier without diplomas.
My father left HS and enlisted at 17, with his mother’s signature, into the Navy, during WWII. At that time, the Navy had a program for sailors to earn a GED while in service, which he did, or after separation.
While I’d agree diplomas are an ideal requirement, I don’t really see the wheels falling off without a diploma. There are many other things more detrimental to our services than this.
When my father was an enlisted man in the US Marine Corps (1936-1940), he had a high school diploma but most of the men he served with did not. Completing high school was much less common in that era.