In North America, there is always much talk about the separation of church and state, however I'm not really thinking about that particular issue (although for the record, I think that we have enough historical evidence to suggest that a powerful church is a dangerous church).
I want to talk about all religion in relation to politics. Before I do so, I think it's appropriate to declare that I consider myself to be a non-theist. I don't believe in a God or gods. I have even less 'faith' in mankind's spiritual institutions, riddled as they are with human flaws. I also don't think that I know everything, but after a great deal of thought my choice is made - and that's the position from which I come to this subject.
In the middle ages (which of course is my age group!) the church in Europe was massively influential; at times monarchs and other forms of government answered to the church, promoted the church's agenda or at least used the church as a moral compass. I can understand why that happened - understand it as historical fact, and I think I understand why relatively unworldly and uneducated people would consider an enormous institution directly connected to God to be the ultimate authority on earth. At the micro level, whether or not the beliefs of Christianity are shared by me, it makes sense that the man or woman in the stinking, festering street would look up to the church.
That a great many people in the modern world seem to put the same trust in religious organizations is, however, something I have some difficulty accepting. These days, especially in Europe and North America, the overwhelming majority of the population has easy access to TV, radio, internet news and social media. Even if, for example, I can't afford a computer, I imagine that I would find it difficult not to notice what happens and is reported via the TV. AND, even if I don't watch TV, the people around me will talk about world events with a breadth of knowledge and insight that would have been impossible even fifty years ago. By saying this, I am of course really talking about what we call 'western' society or developed countries. I'm aware that there are hundreds of millions of people around the world who have no internet access, no TV service and perhaps, if they are lucky, some semblance of a radio service. I understand that there are significant numbers of humans who, in this regard, still live in a very small world of their own village, town or some other kind of settlement.
For those unfortunate people trapped in poverty, I think it makes a lot of sense that they might seek solace or some explanation for their world being how it is - and that religion in some form or other would appear to offer the answers. This last statement betrays my theory about religion in general; it's not a new one but I do have the satisfaction of coming up with it independently. My belief (uh-oh, there's that word again!) is that religion is an invention which is designed to answer the fundamental questions of life, many of which can begin with the words "How?" and Why?". These questions would be the same for a lonely goatherd or a high flying corporate executive; a nomadic tribes-person of the Sahara or a professional athlete.
I'm not trying to make a judgement call here; I'm not saying that any one religion is wrong or bad. What I AM saying however, is that a belief system which depends upon interpretations of anecdotal events, with little or no physical or corroborative evidence to support them, flies in the face of our modern world's scientific and communication achievements. It's a massive argument, of course, much too long to get into here, but hopefully I have explained where I stand on the question of religion.
Now, does religion have a place in politics? Well, the debate about morality is a very involved one but the question of morality driving political policy-making is hard to ignore. My guess (and I can't speak for others, only myself) is that many, most, or even all religious politicians will refer to their religious beliefs as the source of their personal values...by natural progression, the motivation for their political ideology. Whether or not such claims would be true cannot be proven of course, but the question of religion - based morality is a confused and controversial one.
Ardent atheists will - and do - argue that morality based upon religious teachings is a fraud, that modern morality (i.e. usually that extolled in the developed world) is shaped far more by secular influences than by religious values. It is certainly hard to read many passages of the Bible or the Quran and get a sense of modern morality from those works. Nothing has changed in the Bible, for example, since the middle ages, yet the Christian Church has changed almost beyond recognition in terms of it's public moral stance - the recent child molestation scandals of the Catholic church notwithstanding. While not perfect, the Christian church of today is nothing like the bloated, immensely powerful, downright corrupt and evil monster it had become through the Dark Ages and into the Middle Ages.
My point? Religious groups, contrary to their professed assertions, simply - and evidently - cannot be trusted to be correct simply by virtue of their faith. Witness the Taliban's documented activities, witness the Catholic church's current difficulties, witness the Westboro Baptist Church's undiluted hatred of anything different from themselves. Being religious does not give anyone special insight, does not automatically confer an approach of 'goodwill' or automatically provide a benevolent or even particularly wise, perspective.
Religion should, in my view, be kept out of the town hall, the cabinet room and the offices of government leaders (at any level). The evidence of history points to religion sharing a podium with intolerance and a lack of objectivity - not particularly desirable traits for governance. While I would hesitate to recommend that religious beliefs should disqualify a person from holding public office, they should be disqualified from being used as a campaign asset - I strongly disagree with a politician being elected because they profess to belong to any religious group.
Religious politicians are with us forever - there's no getting away from it and maybe that's healthy on the grounds of diversity, however in my opinion, religious groups belong in the political system only alongside the voices of other lobby groups (and the ethics of lobby groups is a whole other matter). Politics is, in my view, about the practicalities of life, not the desire of some to impose their spiritual ideas upon the rest of us.
I want religion kept separate from political office and policy but I doubt very much that it is possible any more. The best I feel able to hope for is that the majority remains aware and watchful for religious encroachment into our political policy-making processes. Having an opinion is one thing; debating it and listening to the opinions of others is helpful - even more helpful is being open to changing one's opinion based upon the presentation of evidence and reasoned arguments. My experience of religion in forty-something years and the reading of history is that religious affiliation and faith tends to preclude openness and a willingness to listen to alternative perspectives. Religious politics is simply legally empowered religion; I don't want to go there.