John Gill Commentary Nahum 2:11

"Where is the den of the lions, and the feeding-place of the young lions, where the lion [and] the lioness walked, the lion`s whelp, and none made them afraid?" — Nahum 2:11 (ASV)

Where [is] the dwelling of the lions ?
&c.] Of the kings of Assyria, comparable to lions for their strength, courage, and cruelty, tyranny, and oppression; such as Pul, Tiglathpileser, Shalmaneser, and Sennacherib. So the Targum,

``where are the habitations of kings?'' these are the words, either of the prophet, or of the people that had seen this city in its glory, and now see it in its ruins; and so desolate and waste, as that it could scarcely be said where it once stood: and the feedingplace of the young lions ?
the sons of the kings of Assyria, the princes of the blood, and who were of the same blood, temper, and disposition of their ancestors, and were born, brought up, and educated, in Nineveh the royal city. So the Targum, ``and the dwelling houses of the princes,'' or governors: where the lion, [even] the old lion, walked :
not Nebuchadnezzar, as Jerom, who entered into Nineveh the den of those lions, or seat of the Assyrians, and took it, and walked about in it, as the conqueror and possessor of it; but rather Nimrod, that old lion and tyrant, if he was the first founder of this city, as some say; though it does not seem so much to design any particular person, but the kings of Assyria in general, even the most cruel and savage, as the old lion is. So the Targum in the plural number, ``whither the kings went;'' and the lion's whelp, and none made [them] afraid :
there were none to resist their power, curb their insolence, and put a stop to their cruelty and oppression; or make them afraid of pursuing such methods. The Targum is, ``there they leave their children, even as a lion that continues in hunting with confidence, and there is none that terrifies.''