I'm reading the book The Myth of the Christian Nation, by Gregory Boyd. This is an interesting work. It came out of a sermon series he preached 5 or so years ago in which 20% of his church left.
The thesis of this book is that in the world [and especially in America] we assume that our country is blessed above all others by God, and that the role of Christians is to perserve the "Christian values" in our mainstream culture. The problem with this, Boyd argues, is that America [nor any of the other kingdoms of the world] is not inherently Christian. THUS, when talking about the Kingdom of God, we're not talking about the United States of America.
This is his reasoning. There are two types of kingdoms out there [and I'm totally paraphrasing his stuff, so if you want quotes, follow the link of the book to Amazon, but it, and read the stuff yourself]: Kingdoms which use power to control people, and Kingdoms which do not. ALL governments of this world use power to control us. Even if there are elections and we can decide the laws, those laws are then enforced by force and power. This is not the Kingdom of God.
The Kingdom of God is a place where grace rules the day. The Kingdom of God is a place where love is the greatest value. The Kingdom of God is a place where the poor are valued as much as the rich. Where the weak are look upon as blessed. This kingdom is vastly different than the kingdoms of this world. The kingdom of God is a place where the values are different. Success is not a measureing stick that is used to place judgment on anything.
Thus we need to, when thinking about the Kingdom of God, use a different set of expectations. We must understand it is something completely different something completely not of this world [John 18.36]