Absolutely not. If separationism means anything, it is that people should have the freedom to act publicly on their religious beliefs without coercion from the state. This would include the right to vote and run for public office in accordance with one's religious beliefs. More generally, separationists are aware that religion has profoundly influenced the culture and morality of this nation; it is natural and proper that people would identify with that influence, and use it to order their lives.
Nevertheless, the First Amendment had the effect of forbidding anyone from using the government to pass sectarian legislation (i.e., legislation designed to establish religious belief by law). One's decision about how much we should spend on welfare, for example, might well be influenced by one's religious beliefs, but it would surely be unconstitutional to require people to attend church as a condition of welfare. Granted, it is sometimes difficult to know just where to draw the lines between sectarian and non-sectarian legislation, but such lines do need to be drawn. Separationists believe that the religion clauses of the First Amendment serve as an adequate guideline for resolving most of these disputes.