I know two things. 1. We are now already using heat mask measures, even when we are very young civ in terms of Kardashev scale. We already use simple slit heat

I know two things. 1. We are now already using heat mask measures, even when we are very young civ in terms of Kardashev scale. We already use simple slit heat emitters in military tech (many Stealth planes have slit nozzles and for example, Leopard tanks also use slit exhaust for same reason). 2. Even we now know about possibility of laser heat, which could emit heat directly with very high focus. In conclusion, idea is, to surround whole civ with heat mask blanket, and make all heat exhausts directly focused on directions, where no observer expected. BTW this could be evidence of mature Civilization, when see strange space objects, which looks like Black Hole in most directions and extremely bright in some "featured" directions. Second, looks like our development now is very slow, because it should be on early stages (Kardashev scale), and old civ's should know this. And I now support theory, that we are fortunate to be far enough, so stronger civ's are not interested in spending resources to limit our development. I even consider might be exists some preservation pact between old Big civ's, to avoid touch young civ's, for some purposes like scientific, or arts. So yes, basically, I support Zoo theory.