I’m not sure if I’ve understood your intentions correctly as English is not my first language, but what you are describing in the ‘Tag:bunker_type=bomb_shelter’ entry is a bomb shelter for civilians.
I live in the Korean Peninsula, which is currently under tense military confrontation between North and South Korea, and I am aware of several different types of government-managed bomb shelters.
I have also done some research on bomb shelters in other countries, especially Taiwan, which is still under tension, in order to write this entry.
Some of these facilities are open all the time, some are used for other purposes during normal times, and some are opened when there are signs of war.
These bomb shelters can be broadly viewed as “military” facilities, and I do not believe that “military” necessarily means that they must be used and managed by the military.
I don’t think it’s possible or reasonable to categorize bomb shelters with a tag that reflects all of the different conditions that apply to them (because the conditions vary so much, I think the term should be used rather generically).
I add to the previous discussion of shelters (for disasters). - Clean up the types of ‘shelter’ on the OSM wiki