The Lord will come into Egypt quickly, with judgement. There will be anarchy, war, division among all the people. They will look for foolish diviners and easy answers to their problems (v. 1-3)
The land will be conquered by a cruel master. Either by design or nature, the land will become barren, and unable to support life. There will be no resources (v. 4-10).
The glory of Egypt is removed (v. 11-16).
They will fear their coming destruction, knowing it has been decreed to them by the Lord (v. 17).
The righteous will come, people will be converted, the nation redeemed and saved by the power of the Lord, blessed as Israel (v. 19-25).
I'm a little lost on the continuity and connection between v. 17-20. I'm not sure those breaks are accurate. Something doesn't make sense.
Isaiah 19:1, Exodus 12:12
I remember hearing somewhere a comment made that the Lord would smite all the gods of Egypt, and that the wonders sent among the nation were things that their gods were specifically in control over, according to their beliefs. Destroying the faith of their idols. There was a purpose to each plague, and they were chosen specifically.
If there is free movement between the two nations (Egypt and Assyria), that means a few things. For one, there is some peace and stability in the land, that they can freely move between the two. It would also imply that there is a working infrastructure (highways) – the nations are not lying in rubble. Finally, if they are in service, doing good works, then that means that their lives are stable and settled – they have the means and time to be able to do community and/or ecclesiastical work. Also, they are tolerant of other nations and lands (Assyria, who they were usually at work with), meaning they have learned some sense of unity.