BIshop Pierre Whalon says that it is both naive and impossible to separate religion and politics.
...it should be clear from human history that religion and politics cannot be separated. Both of them arise from the fact that we Homo sapiens are communal beings: we cannot live completely alone. Every aspect of what makes us human develops completely from living in a community, beginning with the family. Anthropologists are clear that having a sense of the sacred (whatever one makes of it) is one of the fundamental aspects of what differentiates Sapiens from other hominids. Politics is how we order our common life.
It is therefore impossible to separate them, and anyone who claims it can and should be done is either lying or hasn't thought it through. It's pretty basic...
There are a lot of national elections happening this year around the world. Name one where religion is not a significant factor, even if it is not blaringly obvious, as it is in the United States. France, for instance, will elect a new president next month, and it is clear that Nicolas Sarkozy has been enlisting the help of religious leaders, including Muslims as well as Catholics and Protestants, in his re-election campaign. Just as obviously, his main rival, Socialist François Hollande, has been complaining about Sarkozy's alleged infringements on the République laïque, the legally secular, rigorously neutral French Republic. Atheists are religious too.
As a religious leader, I have often been told, as I said, to "stay out of politics." But that is impossible for a Christian, since Jesus of Nazareth's execution -- a crucial moment in human history for us -- was blatantly political. Proclaiming his Gospel therefore has inevitable political consequences. When Christians began reciting Kyrie eleison ("Lord, have mercy") in the liturgy, it was a powerful political statement. That is what a loyal Roman said to Caesar when coming into the emperor's presence. To repeat that in worship clearly states that God, not the emperor or other political ruler, is in charge. Can't get more political than that, especially considering that Caesar was thought to be divine himself.