These verses appear to be directed to ancient Babylon. The word “besom” (v. 23) means the same as our modern word “broom.” The context is the same as for those who live in the promised land (the Americas) who “shall serve God, or they shall be swept off when the fullness of his wrath shall come upon them” (Ether 2:9–10).
The King James text says; “I will break the Assyrian in my land” instead of the bolded “bring” the Assyrian,”(v. 25). The message is the same with either word. There is another insignificant deletion in the King James text (v. 26). The Assyrian represents the Gentiles, and the purpose of the Lord is to give all the gentile nations an opportunity to be numbered with Israel (see 3 Nephi 30:1–2). The judgments of God will be poured out upon those who reject this opportunity. Mormon made a similar prophecy concerning the Gentiles after they have an opportunity to accept the gospel.
22 And then, O ye Gentiles, how can ye stand before the power of God, except ye shall repent and turn from your evil ways?
23 Know ye not that ye are in the hands of God? Know ye not that he hath all power, and at his great command the earth shall be rolled together as a scroll?
24 Therefore, repent ye, and humble yourselves before him, lest he shall come out in justice against you—lest a remnant of the seed of Jacob shall go forth among you as a lion, and tear you in pieces, and there is none to deliver. [Mormon 5:22–24]
Isaiah’s prophecy of Babylon was given in the year that king Ahaz died (v. 28), but it was not fulfilled at that time. Whether the whole prophecy concerning Babylon was given at that time or the verses that follow is unclear, but it does not really matter, since both have reference to a future and not an immediate time.