We do not ask for salvation from politics. We cannot expect politics to do this either for us or for others.
The tradition of the Church has always indicated two ideal criteria for judging every civil authority and every political platform:
a) libertas Ecclesiae. A power that respects the freedom of a phenomenon so sui generis as the Church is for that very reason tolerant towards every other form of authentic human aggregation. The recognition of the role of faith, including its public role, and the contribution it can make to man’s journey is, therefore, a guarantee of freedom for all, not only for Christians.
b) the “common good.” A power that it is conceived as a service to the people has at heart the defense of those experiences in which the desire of man and his responsibility can grow as a function of the common good, through the construction of social and economic works, in keeping with the principle of subsidiarity, well knowing that no program will enable it to be fully realized because of the intrinsic limitations of all human effort.
For a bit more commentary on them, check out Rick Garnett's post over at Mirror of Justice.