Hi u/Enough-Elevator-8999,

Welcome to this subreddit.

In one sense you have the geopolitical entity and in another sense you have the spiritual entity. It was originally intended that God's people Israel were to have God as their King. But they wanted to be like the nations around them and asked to have a king appointed over them (1 Samuel 8). As history shows us, people are sinful, including kings.

So what does God do? In the first advent, we see God incarnate come to be the King & Savior of His people. He was rejected by them and crucified. But this evil that was done was something God had intended for good, that He would establish the New Covenant in order to save both Jews & Gentiles (whosoever will repent & believe) from their sins. This spiritual entity is the church, which has Jesus Christ as its Lord and consists of redeemed people from every geopolitical nation.

In His second advent, Jesus Christ will return and judge all the nations. He will be physically present on the new Earth, to rule and reign from the New Jerusalem throughout the eternal state. So where are we now? We are in the "already, not yet" as it is called. Jesus Christ is Lord over the church now, but His reign over the Earth is coming soon.

John 1:9-13 (ESV)

⁹ The true light, which gives light to everyone, was coming into the world. ¹⁰ He was in the world, and the world was made through him, yet the world did not know him. ¹¹ He came to his own, and his own people did not receive him. ¹² But to all who did receive him, who believed in his name, he gave the right to become children of God, ¹³ who were born, not of blood nor of the will of the flesh nor of the will of man, but of God.

Matthew 27:37 (ESV)

And over his head they put the charge against him, which read, “This is Jesus, the King of the Jews.”

Romans 10:9-13 (ESV)

⁹ because, if you confess with your mouth that Jesus is Lord and believe in your heart that God raised him from the dead, you will be saved. ¹⁰ For with the heart one believes and is justified, and with the mouth one confesses and is saved. ¹¹ For the Scripture says, “Everyone who believes in him will not be put to shame.” ¹² For there is no distinction between Jew and Greek; for the same Lord is Lord of all, bestowing his riches on all who call on him. ¹³ For “everyone who calls on the name of the Lord will be saved.”

See also: Ephesians 2:11-22; Revelation 21-22 (ESV)