The Church and the Lure of Power

Just came across this interesting quote from Stanley Hauerwas:

To be among those who praise God as the ruler of this world, however, has often tempted Christians to think they are or must be in control if this is in fact God’s world. Caesar’s throne can be or must be usurped to insure that justice is done. The difficulty of being a creature wounded by sin is forgotten. Indeed, we forget or deny that we are creatures subject to the illusions we create to insure our significance. As a result, we lose the necessities that create imaginative alternatives that make it possible for us to live without denying the difficult task of acknowledging our humanity and that of our neighbors.
Stanley Hauerwas, Approaching the End: Eschatological Reflections on Church, Politics and Life, 151.

I think the question is how “realized” can our eschatology be and how does this effect our idea of political theology in a secular state. A theocracy is impossible and Christendom is no more. However, if we try to maintain a prophetic voice from the margins of society rather than from within the bowls of power, what happens when people find reason to turn the prophetic vision into actual law?  In other words, if the prophet calls people to do something, can we complain if people then try to do it?