Terminology is not easy to deal with. Cut Donald some slack.
Most of us have done similar things in references to all our armed forces as a class. I use the word "troops" generically, although that's not all that accurate either. When I'm thinking about it, I use "military personnel." Lately, since we've been dealing mostly with Marines, I've been able to use "Marines."
I read a lot of milblogs, and know that some people are really anal about the terminology. That's certainly their privilege, I suppose, but I don't think using "soldiers" as a generic detracts that much from the actual points we're trying to make around here.
At worst, such nitpicking gets irritating, as when some people insist on using "his or her" all through a document.