I know that back in the early 90’s there were definitely Marines using aas. It wasn’t widespread in my experience but there was not the same access to information and product as there is today. I can’t imagine that use isn’t well known today.
Makes sense though right? We definitely don’t want men who are tasked with walking the wall to have an unfair advantage over those who wish to do us harm. Equality and all being as critical as it is.