Often in the political sphere and other spheres Christians try to expound views that are godly. They attempt to argue for change.
Often the issue is that the culture has already rejected most of the presuppositions that we argue from. We cannot win debates in culture because all our presuppositions are rejected.
The church needs to accept that it is not the dominate force today in the western world. The church will be more healthy once it realizes that it is on the margins of society today.
Often the church wastes a great deal of time in meaningless dialogue because the church feels it has sway. The church needs to stop expounding change to the culture on the basis of argument and focus on spreading the gospel.
The church's presuppositions are being radically rejected because Jesus is being rejected. If we want to change society we must first have society meet Jesus in a meaningful way.
Only by re-introducing true biblical faith into the culture can Christian's hope to have culture listen to messages of change in relation to society. The gospel is foundational to all Christian ethics.