I recalled a quote from President Reagan about saluting, so I looked it up:
"And so, I know all the rules about not saluting in civilian clothes and so forth, and when you should or shouldn't. But then when I got this job -- (laughter) -- and I would be approaching Air Force One or Marine One and those Marines would come to a salute and I -- knowing that I am in civilian clothes -- I would nod and say ‘Hello’ and think they could drop their hand, and they wouldn't. They just stood there. So, one night over at the commandant's quarters, Marine Commandant's quarters in Washington, and I was getting a couple of highballs, and I didn't -- (laughter) -- know what to do with them. So, I said to the commandant -- I said, ‘Look, I know all the rules about saluting in civilian clothes and all, but if I am the Commander in Chief, there ought to be a regulation that would permit me to return a salute.’ And I heard some words of wisdom. He said, ‘I think if you did, no one would say anything.’
"So, if you see me on television and I'm saluting, you know that I've got authority for it now -- (laughter) -- and I do it happily."