In certain circles, there is a tendency to relate the Kingdom of God so closely with economic theories that a particular theory is championed as closest to the kingdom of God. If the certain conservatives unduly try to find free market applications to Jesus' parables, then other circles try to extrapolate a macro-economic theory from the principle of the kingdom of God.
Given the recent abuses of capitalism and the proclivity of capitalists to associate the free market with greed, Christians often denigrate the former because of the Bible's clear rebuke of the latter. But is the a proper view of economics? What's more, does the kingdom of God mandate a certain economic theory.
Here is an excerpt of lecture at the Cato Institute by Jay Richards, author of Money, Greed and God: Why Capitalism is the Solution and Not the Problem.
In this excerpt, Richards covers two of his points:
(a) evaluating consequences (unintended and otherwise) not just intent--which he calls the piety myth "that you can only focus on intent". Good intentions can lead to bad policy and vice verse;
(b) The greed myth: that capitalism is based on greed. he shows that while certain authors defending the free market have equated self-interest in the market with greed, this is indeed not what Adam Smith meant by 'self-interest'. He argues that capitalism itself is not immoral--indeed it is the best option for spreading part around rather than consolidating power. Given fallen humanity, history has demonstrated that power corrupts and absolute power corrupts absolutely. As long as the 'rules of capitalism' is set up right, it can channel the evil elements of greed, which Richards argues is not the same as saying capitalism is based on greed.
You can watch the whole forum here, it's worth your time:
It includes a response by Doug Bandow. The Q&A at the end is interesting as well.
At one point in the Q&A, Jay Richards even mentions the already/not yet aspect of the Kingdom of God in the New Testament. He notes that when humans try to create the kingdom (particularly through political means), instead of bringing heaven down, they bring hell up. His point: you have to compare live alternatives captialism vs. Stalinism; not to the kingdom of God, which only God can bring.