God’s judgements, when they are truly from God and not someone simply declaring they are from God, are not punitive, but disciplinary. In other words, God does not punish for the sake of punishing, but does so in order that we would recognize our errors and repent. Throughout Isaiah (and all the prophets) there are numerous oracles of judgment about different nations and the Jewish people. This passage of Isaiah, though, shows that those judgments are not in order to wipe these nations off the map, but to create a better future for them:
18 On that day, there will be five cities in the land of Egypt that speak the language of Canaan and swear loyalty to the Lord of heavenly forces. One of them will be called “the city of the sun.” 19 On that day, there will be an altar to the Lord within the land of Egypt, and a standing stone for the Lord at its border. 20 It will be a sign and a witness to the Lord of heavenly forces in the land of Egypt. When they cry out to the Lord because of oppressors, God will send them a savior and defender to rescue them. 21 The Lord will make himself known to the Egyptians; the Egyptians will know the Lord on that day. They will worship with sacrifices and offerings, making solemn promises to the Lord and fulfilling them. 22 The Lord will strike Egypt; striking and then healing. They will return to the Lord, who will hear their pleas and heal them. 23 On that day, there will be a highway from Egypt to Assyria. The Assyrians will come to Egypt, and the Egyptians to Assyria; and the Egyptians will worship with the Assyrians. 24 On that day, Israel will be the third along with Egypt and Assyria, a blessing at the center of the world. 25 The Lord of heavenly forces will pronounce this blessing: Bless Egypt my people, and Assyria my handiwork, and Israel my inheritance.
God wants even Egypt and Assyria to be a part of his people. This prophecy came to fruition with the creation of the Church and the spread of Christianity throughout the world. There are churches in all of these parts of the world today, including Heliopolis (city of the sun), a suburb of Cairo. This is Good News!