I have to agree with
@theg*ddam*hoi2fan in this debate, even if some involvement of religion in government has brought good things, there has been alot more horrible things brought around by the inclusion of religious and theocratic beliefs into governments.
Obviously, if one were to pile all of the good things the interaction of religion and politics have done on the left side of a scale, and all the bad things on the right side, the sheer imbalance towards the right would flip the scale over. This is because humans are corrupt, blind, and hypocritical.
Here’s the thing though, fundamentally, the definition of politics is “of the people.” It’s literally the name (from
polis). And
what is more vital to people besides their religions and beliefs? This is not a hypothetical. Most would say that it’s a matter of critical, if not necessarily vital, importance. Roughly right in the middle, at the love and belonging tier, of Maslow’s little pyramid. I disagree; I think it is right at the very bottom, among the most basic physiological needs of the individual. What else can I say, having witnessed myself people denying themselves food, shelter, and sex for faith? And the sheer number of documented examples of people choosing pain and martyrdom for the sake of belief? One cannot separate the people from what they believe; even the Soviets and Chinese, offering substitutions rather than separations, failed.
Queen Elizabeth I once said “I do not make windows onto men’s souls.” Good for her; that was her belief, and at the time, England was a politics of one. As Parliament gained power though, the state became more invested in religion, until suddenly they were in a civil war over it. The Founding Fathers were of a group that, by and large, studiously avoided religion. And they got away with it in their lifetimes because of a combination of high esteem they were held in, and a seriously restricted franchise. As American history moved forward though, religion played a larger and larger role as the franchise expanded, until it indirectly caused the American Civil War. One could say the apogee of religion in American politics occurred on November 19th, 1863 when Lincoln spontaneously added “under God” to the speech he was giving at Gettysburg (his draft didn’t have it).
This might be a controversial statement, but it seems clear to me that the political character of the US has become more religious, and specifically more Christian, with each expansion of the franchise, with each leveling of the elites, and with each advance towards a hypothetical perfect democracy. I see no other way to explain this than by saying that while one can occasionally find an individual with not particularly strong convictions or completely different beliefs and outlooks, particularly among the upper classes, among a people and a society as a whole, one cannot escape the faith of the people, whatever it is.
I guess what I am trying to say is that the involvement of beliefs and religions in politics may be good, it may be bad, but it is, certainly, inevitable. One does not get a democracy inspired by the Koran from a Christian populace, one does not get a nation on Confucian principles from among the Hindus, and one does not get a state on agnostic or secular principles, unless the people themselves are agnostic or secular. When the people are of a religion then, the state cannot be a true democracy, representing the true politics of the people, unless it is likely.
The United States, sir, is a Christian nation. This has been masked in various artifices over the years, but it keeps on bleeding through, and it will continue to be so until the populace ceases to be Christian. Perhaps this is good, perhaps it is not good, regardless, I see no higher thing any individual can do in the present situation than to work for the most perfect Christian state possible.
I'm thrilled that you're enjoying Blue Skies thus far and hope I can keep up the good work for you. 
