'Heaven' is a frame-of-mind; it's both a physical locale and a spiritual one. It should not be confused with the 'heavens' (sky/space). I AM in heaven right now. I AM very close to GOD: the 'universal quantum computer' and loved ones (I have the world's best girlfriend), I live in Miami (paradise), and work as a musician.
2,000 years ago, there was no other form of government then kings and their kingdoms. Since 1776, GOD and the Christ's preferred form of governance is democratic-republics. Can anyone even want to imagine a king of the United States? Therefore, we must STOP referring to the "kingdom of God" or "the Christ returning as king of the world". The 'governance of God' works. Christ 2 will be recognized as the head of the Christian churches, and Jews and Muslims will recognize him as well as the spokesman for the One GOD.