[Isa 14:4, 17 NLT] (4) you will taunt the king of Babylon. You will say, "The mighty man has been destroyed. Yes, your insolence is ended. ... (17) Is this the one who destroyed the world and made it into a wasteland? Is this the king who demolished the world's greatest cities and had no mercy on his prisoners?'
I would understand the "king of Babylon" in Isa 14 to be the titular king as opposed to an actual king, because the last king of Babylon was not the king who conquered many cities. More specifically,
- The king who "has been destroyed" is a prophecy about the last king of Babylon which would be either Nabonidus (556 BC - 539 BC) or his son and co-regent Beshazzar (553 BC? to 539 BC).
- The king of Babylon who "destroyed the world ... demolished the greatest cities" would be Nebuchadnezzar II (the "great") 605 BC - 562 BC. Nebuchadnezzar conquered Charchemish, Egypt, Assyria, Phoenicia, Judea, Cilicia, and kept Jehoiachin in prison for 37 years (Jer 52:31).
Thus, here as in many places in Scripture and Hebrew idiom, the "king" stands for the kingdom. Put another way, Babylon was personified by its king as we see in other places where Jacob is the personification of Israel, Esau is the personification of Edom, etc.
I also think that while Babylon wasted several cities, it did not make the world a wasteland; thus, Isa 14:17 is rather poetic and thus, hyperbolic.
That king of Isaiah 14:4 KJV perfectly fits Titus. He was that King of Babylon, diverse from, and extended by changes to the little Horn of Daniel. He is the eleventh king of the powerful world-order of Rome, being the natural born son of, and natural heir to Vespasian--the tenth king--who was destroyed neither in anger, nor in battle. Daniel 11:20 demands:
Then shall stand up in his estate a raiser of taxes in the glory of the kingdom: but within few days he shall be destroyed, neither in anger, nor in battle. (My emphasis)
That is very unusual, check out Vespasian's predecessors. They were nearly all killed or died in some manner of strife.
MOREOVER Titus is also the eighth king of that Roman world-order kingdom, beginning with Julius Caesar, according to Revelation 17:11:
And the beast that was, and is not, even he is the eighth, and is of the seven, and goeth into perdition.
Nero was the sixth king of Revelation, and was, at the time of the prophesy to John, in the waning days of his reign as we see in Rev 17:12:
And there are seven kings: five are fallen, and one is, and the other is not yet come; and when he cometh, he must continue a short space.
How can He be the eleventh king of Daniel and still be the eighth king of Revelation?
BECAUSE he (Titus) had to come after the short reign of three rogue civil-war kings who were not acting in the interest of the "glory of the kingdom". Vespasian suceeded the three plucked-up kings, but in the glory of the kingdom because he was a dedicated Equestrian, (Dan 11:20, supra). Those three kings were "plucked up"--effectively eliminated--and therefore, not counted in Revelations tally of kings. No other Roman king or emperor fit's that set of required facts.
The historian of the day, often quoted by many of the religionists today, was a close friend of Vespasian and Titus. In fact, he was made a member of the Royal Flavius family. No wonder, Flavius Josephus, a Jew--who turned against the Jews and favorably toward the two men responsible for destroying the City of Jerusalem in 70 AD--did his best to alter history and times to protect the two scoundrels--the Flauvius father and son--the two kings referred to in Daniel 11:27:
And both these kings' hearts shall be to do mischief, and they shall speak lies at one table; but it shall not prosper: for yet the end shall be at the time appointed. (My emphasis)
The answer to the OP's question is more fully addressed, especially with respect to Isaiah 14:4, in my paper at: