In The Bible As a Human Witness to Divine Revelation, I read James D. Nogalski's "Micah 7:8-20: Re-Evaluating the Identity of the Enemy."
Nogalski's argument---if I understood it correctly---is that Micah 7:8-20 draws from Isaiah 9-12, which concerns God's judgment of Assyria. Nogalski disagrees with those who think that Micah 7:8-20 addresses the Babylonian destruction of Jerusalem in 587 B.C.E., expressing Israel's hope for restoration from exile. At the same time, Nogalski doesn't appear to believe that Micah 7:8-20 was necessarily composed during Israel's pre-exilic period---the part of it in which Assyria was a threat. Rather, his view seems to be that Micah 7:8-20 was post-exilic, and that it was looking back at God's judgment of the Assyrians in history. Nogalski's point may be that Micah 7:8-20 was celebrating God's activity in a historical event---God's judgment of the Assyrians. A parallel that comes to mind would be the Jewish people's celebration of the Exodus, which appears in the Bible and in post-biblical Judaism.
Indeed, Micah's message within his historical context was remembered by subsequent generations of Israelites. In Jeremiah 26:17-29, an elder refers to Micah's prophecy that Jerusalem would be devastated, which, the elder notes, did not come to pass on account of Hezekiah's repentance. In this story in Jeremiah, an elder is referring to an event in history, in which God protected Jerusalem from the Assyrians. Even after the Assyrian threat had passed, Israelites continued to draw strength from the story of God's judgment of the Assyrians.