Moral Resposibility, Bystander Effect, and Grace

A friend wrote in reply to my article Taxation is Stealing, Health Care, and Jesus' Teaching on Caesar:
Nice blog entry, though I am a bit uneasy with the second sentence in the following quote:

"Christians can disagree with the government and express our opinion. In a democracy, it is our Christian responsibility to do so."

This use of "responsibility" triggers my Niebuhr meter.
Is that a bad thing?  Here is the section in question that I have since changed due to my friends persuasive arguments.
Christians can disagree with the government and express our opinion.  In a democracy, it is our Christian responsibility to do so.  We only stop going along with the government when what they propose is in direct violation of Scripture.  This teaching excludes taxation because Jesus taught that we are to give to Caesar financially what Caesar demands.  If Caesar tells us not to love a person, we still love them.  If they tell us to only express certain beliefs, we still express what we feel is the truth.  But when it comes to taxation, we still give to Caesar what is Caesar's, and to God what is God's. 
When writing that sentence, I did think that a cerebral person could have problems with my wording, so it says something good about you.

For starters, the Bible never addresses how we should behave as followers of Jesus in a democracy.  So this is more of a philosophical argument based upon the biblical principles of peace and justice. 

If two of us are in a room, making a decision together, and we decide to commit an unjust act, I would be guilty even if you were the only one that perpetrated the act.  If we are in a group of twenty people who decide on an unjust course of action yet we stand up, disagree, and try to prevent the others from the unjust act, we would be recused from responsibility?  Those who silently acceded the point to the ringleaders and did not stand up against them might not be as guilty as the ringleaders, but they would carry some guilt for not standing up to them?  The dilemma in this concept comes with the dilution that occurs in talking about a community, state, or nation.  In those cases, we are no longer are we talking about small groups where we naturally understand the distribution of guilt.  When we start talking about our responsibility as individuals or as a small community in a group of 300,000,000, we begin to feel less responsible for the decisions of that group.

It is an unfortunate result of the Bystander Effect.  More people involved in a situation causes each individual to feel less responsible for the actions of the group.  We see this in the murder of Kitty Genovese in 1964 and the 2009 gang rape outside of a homecoming dance in Richmond, California.  People don't feel responsible when there are more people involved.  We have a tough enough time saying that we are sorry and taking responsibility for our own actions, let alone the actions of others that we could have stopped.  If we can easily pass sin off, we gladly do so.

History has shown that those who stand up for people's rights can change things.  People could have changed the circumstances for the better in either the case of the gang rape or the case of Kitty Genovese.  It only takes active, small groups to make a difference and divert the course from one of evil to one reflecting God's kingdom.  In our nation, we need more people to stand up for the convictions of peace and justice to reel in the fallen tendency that lures us toward selfishness, overconsumption, and individualism.   

If I do not speak out against the atrocities committed by my nation, then I am responsible for those atrocities.  It is my moral responsibility to speak and act in ways to try and bring about change.  You understand that I am speaking of only doing this in peaceful and non-violent ways; not in ways reflecting the Christian militia that began their trials this morning.  We change this world by prayer, truth, and love, but love means that we stand up for the oppressed, clothe the naked, help the homeless, and look out for other ways to reflect God's light in this world. 

Although I do not expect my nation to behave in a Christian manner, it is Christians who hold us back from the cliff of complete selfishness and moral destitution.  That might be arrogant to say.  Maybe it needs to be reevaluated.  But righteous people, maybe of all religious persuasions, are the people who stem the tide of depravity that inevitably leads to cultural destruction.

And in the end, I rely on salvation by grace because I am responsible for some terribly atrocious acts. 

I have never read Niebuhr, although The Responsibility of the Church for Society seems to be a good place to start.  I just googled his name and responsibility; however, I did not have time to read him before writing this and will not tomorrow as I have an insanely busy day.  But I look forward to.  Is there anything else I should read in regards to this?