As we journey through Isaiah 13 – 27, you must not think these are only denunciations of foreign nations. Some of them, like Babylon, are condemned for their pride. Others, like Philistia and Assyria are to be destroyed without stated reason, the cause being evident in their historical oppression of Israel.
But within all this destruction is renewal. A way is being made for non-Israelites to come to God, and that thought is reinforced in chapter 19.
God is not just the God of Israel. He is the only God there is. Therefore, he must be the God of the Egyptians too. Egypt, however, has not acknowledged him. For this, Egypt is to be ruined with disasters natural (drought, famine) and political. Through it all, however, the Lord is building a way to Him that passes through Judah all the way to Assyria (vs. 23) linking all the nations to the people of God. I note also the approved presence of a place of worship in these countries. This is specifically forbidden by Old Testament law, but God (through Isaiah) is looking to a new day and a new time when people from every nation will belong to Him and worship Him wherever they are. It is the time Jesus talked about with the Samaritan woman in John 4, and it comes to pass with the coming of the Church and Christianity.
In the sight of God, the political correctness that encourages people to hold allegiance to the faiths and ways of their cultures, even in addition to the ways of the Lord, is foolish. To worship anything but the God of Israel, and follow any way but His is the path to certain ruin.