Dan Hughes comments:
the challenge here (i have not read Michael's article--only the snippet you quote) is the classic revolutionary-establishment cycle. the idealization of the radical as if it were a utopian end in and of itself is to miss how the radical is defined by the establishment that it becomes if/when it overcomes the particular establishment it is defined against. at that point the radical slowly calcifies into an establishment (Iran, Cuba, China, USA, ...Christianity). There is an endless cycle of an establishment posture of stabilization and a radical posture of critique.
i believe that this is part of the reason that Jesus is not a political utopian. even the most oppressive regime was granted whatever it claimed to own (give to Caesar what is Caesars). it was only what was God's (the life of the people--community) that was outside of the establishment's ultimate control--even if at times it seemed so otherwise.
this kingdom utopian position may be apolitical, but the people who inhabit a kingdom utopian position are not. it is the work of communities of people to come to agreements that make for a step toward that ever elusive "good" society that we all desire (i am not implying an always progressing macro social evolution here). seeking after justice and mercy at a societal level is carried out by aligning oneself with others in positions, parties, governments and the like to create just structures of existence and good laws of governance.
it is impossible to create an algorithmic set of logic to determine how one goes about engaging the wider political situation. postures of stabilization are what enable jobs, judicial constancy and secure social environments. postures of critique are what engender sympathy for the marginalized, system checks and balances and chaos enabling social evolution.
what would Jesus do? i think he would turn over the tables of the religious elite. what other activism do we have as an example from Jesus?
personally, i am not a subscriber to the "WWJD?" system of ethics. i think that it is impossible to adequately answer that question. i prefer: knowing a little about what Jesus did what are you going to do?
WWJD? seems never to get to a place of moral action. KALAWJDWAYGTD? presumes action.