should we be relevant?

My question in ethics today was, should Christians insist upon social relevance when developing ethics or in responding to social issues. I raised the Question because I was reading a book for class written by John Cobb, and he was fairly insistent upon developing an ethics that was relevant to the world at large, possibly in hopes of guiding the culture toward a Christian end, if not necessarily by Christian means. Of course, one has to ask if unethical means justify an ethical end.
For example, many Quakers voted for either John Kerry, or the Green Party in the last election as a response to the horror of the Bush administration. When questioned about the ethics of voting for someone who would continue the "war on terror" and was totally absorbed in a quest to defend an American way of life that is inherently oppressive to millions, if not totally obscene in it consumerism, many said it was a matter of getting Bush out of office. Oh, I see, the lesser of two evils route.
Yet, isn't participation in the American electoral system participation in an unjust system. Did not a vote for John Kerry undermine any real chance that an alternative voice to the American political spectrum would be heard. And, aren't we ethically wedded to challenging every injustice at the core, such as the illegitimacy of most claims to authority and power made by any government that refuses to value life when it comes at the expense of profit or individual freedoms? and don't get me started on the dope smoking hippies of the Green Party! Ok, some of them are nice folks...
Anyway, if voting for the liberal anti-war agenda personified in the form of Dennis Kucinich is being relevant to our society simply because it is participation in the liberal democracy that holds the world at bay with nuclear weapons and Baywatch, no thanks. I might rather watch Baywatch... or the Super Bowl. Then my opinions will not only be relevant to most Americans because I am culturally informed, but because I hold on tightly to those values that suggest the right to oppress and objectify women ethically trump any woman's right to deprive me culturally mandated bliss.