As regards religion and politics, let me just put in my two cents.
The reason there's separation of church and state in the organizational structure of this country is because both institutions have the same goal, to control the behavior of their members, and when they behave in concert, individual freedom doesn't have a chance.
Why?
Well, I begin with the assumption that human existence is confronted by a fundamental conflict--the urge to direct the behavior of others while remaining free to behave autonomously, to do one's own thing without any cognizance of what others want. The conflict is one that cannot be permanently resolved because, if others are to follow directions, then each individual has to be willing to follow directions as well.
There are actually a couple of strategies for resolving this conflict temporarily. The easiest is for individuals to just take turns giving and taking direction. Of course, that requires not only conscious memory but a certain amount of stability within a group so the members can be assured that individual members will be available later to take their turn at doing what they are told.
Another strategy for resolving the conflict is to pretend that the direction of behavior is actually coming from somewhere else. In a secular society, such as this nation has been set up to be, the source of "correct" behavior is located in the laws and legal system that has been constructed out of the consensus of the community as a whole. The problem with this construct, however, is that it is very easy to manipulate and to manipulate it to such an extent that the consensus or agreement on which it is based can be destroyed by a small number of people in a relatively short period of time. And when that happens, when the people no longer agree to have their behavior directed according to law and legal precedent, then the backup system usually relied on to 'force' compliance is the power of the gun.
Another alternative available to resolve the conflict is to ascribe the source of direction to a higher, extra-social power. We usually refer to this as religion when it is organized into a formal body of directives. What happens when religious directives become too onerous is that the individual can respond by rejecting the directives, while the social group whose adherence to authority is challenged has the option of either expelling the recalcitrant members or, in some cases, putting him/her to death. It is the use of this option by some fundamentalist Islamic societies which we in the West are inclined to object to. The execution of individuals who fail to conform their daily behavior to the god-given directives as interpreted by men violates our sense of individual autonomy and freedom most severely.
What makes the enforcement of some religious directives different from the directives enshrined in Western legal systems, is that individuals can be exterminated in the former for failing to fulfill some obligation--i.e. for not doing as they are directed--while the Western legal system generally reserves execution for individuals who do something they've been told not to do.
The reason many people prefer a body of directives that are assumed to have an extra-social source is actually two-fold. On the one hand, it enables individuals to disclaim any responsibility for the directives they utter (it's not my will, but the Lord's that's ordering your life). On the other, resistance to the orders is not personal. That is, an individual is free to resist complying by arguing that the interpretation of the religious directives is flawed.
Another reason for the preference for extra-social or religious directives to be favored by many people has to do with the assumption that humans are incapable of doing 'good'--i.e. behaving an a socially acceptable manner--unless they are directed by a body of rules and regulations. In this case, the natural conflict inherent in the inclination to give direction but to act autonomously is taken as evidence that the human individual is by nature 'evil' and must be forced to conform his/her behavior to social directives. In other words, disobedience is ipso facto evidence of man's "fallen" nature or evil ways.
For whatever reason, the temporary resolution of conflicting interests by taking turns hasn't been generally recognized as a viable strategy. Perhaps that's because an awareness of time and the relevant sequence of events has only recently evolved in the human brain. That it's not a critical faculty may well be attested by the fact that conscious memory is rather late to develop in the process of human maturation and rather likely to disappear as individuals age. On the other hand, it's actually possible an awareness of time and sequential behavior isn't ever universally present--perhaps only peculiar to some.