The US is not a theocracy.

The Founding Fathers made certain that freedom of religion was enshrined in the US Constitution. That means you may believe as you choose. You may choose to not believe as your neighbor. But when it comes to legislation, there has to be serious review as to whether the law will impinge upon personal freedoms. We have legislated for the common good while recognizing there are limits to what a person may do regarding religion. The most common cases have addressed religious beliefs v. racism (Bob Jones Univ. v. US,) a myriad of cases addressing the illegality of child marriage and sex, and parents refusing medical treatment for their children. The state has exerted that the welfare of the individual or the mores of the society must be considered. Further the state has turned to scientific evidence to ensure abortion remains legal and evolution is taught and not pseudoscience or non science.