What does Isaiah 23:9 mean?

A question has been asked after the shocking destruction of the city of Tyre: Why did this happen and who is responsible (Isaiah 23:8)? The expected response would have been to blame the Assyrians, or Alexander the Great, or some other warrior nation. Isaiah doesn't mention any of these invaders. Rather, he makes clear that the Lord of hosts is ultimately responsible for the destruction of Tyre. The God of Israel has "purposed" this fate: He has planned and arranged to bring doom on that once great city.

Why did the Lord pour His judgement on this city? Tyre's arrogant egotism and love for the honor it received from around the world earned the Lord's anger. The people of Tyre were full of themselves and self-glorifying. The Lord calls all people to humble themselves and to depend on Him alone. Those in Tyre believed that they could not be destroyed because their city had been established for so long on the earth. They believed their adventurous spirit and commercial success made them essential. The Lord showed them, and the rest of the world, that was not the truth.

Isaiah's oracles involve nations of the world, yet they are not written "to" the world. They were given as messages to the people of Judah. The Lord wanted Judah to understand that rescue from God's judgment could never come from any of the neighboring cultures. Their salvation could be found in the Lord alone. It didn't matter how strong or ancient or rich a city or nation might be. The Lord was stronger than all of them. Only He was worthy of the trust and hope of His people.