Well, if you identify them then you might have to do something about it. But it's not clear there's much to be done. Sometimes it's easier to deny or just not mention that someone is acting in a hostile way. The example I often think of is Iran firing missiles at U.S. warships during Operation Praying Mantis, and then, as Wikipedia puts it: "The Pentagon and the Reagan Administration later denied that any Silkworm missile attacks took place, possibly in order to keep the situation from escalating further - as they had promised publicly that any such attacks would merit retaliation against targets on Iranian soil."