There is no tag summary for military-cryptography. There are only three questions with that tag. Only one of those do I feel has a remotely "military" feel to it. What should this tag be used for or should it even be a tag?
I could see the military-cryptography tag being useful for questions about cryptosystems designed and/or used mostly within the military, as opposed to those designed by the open academic crypto community.
Of course, the big problem with such questions is that the details of such systems tend to be classified, so — aside from historical systems that have been declassified — all we have to go on is rumors, leaks and conjecture.
In any case, none of the current questions using the tag seem like a very good fit for it. I already removed it from this question, along with a bunch of other random tags that had little if anything to do with the question. Of the remaining two questions, this one should probably be retagged as standards, plus possibly something more specific (though I'm not sure what). As for the last one (which I believe introduced the tag), it does kind of make sense there, even if it doesn't quite match how I would personally envision the tag being used. Anyway, I wouldn't object if someone just removed it from all those questions.