Reasonable minds can disagree about how to apply the Religion Clauses in a given case. But the goal of the Clauses is clear: to carry out the Founders’ plan of preserving religious liberty to the fullest extent possible in a pluralistic society. By enforcing the Clauses, we have kept religion a matter for the individual conscience, not for the prosecutor or bureaucrat. At a time when we see around the world the violent consequences of the assumption of religious authority by government, Americans may count themselves fortunate: Our regard for constitutional boundaries has protected us from similar travails, while allowing private religious exercise to flourish. […] Those who would renegotiate the boundaries between church and state must therefore answer a difficult question: Why would we trade a system that has served us so well for one that has served others so poorly?

Sandra Day O'Connor (b. 1930) American attorney, politician, Supreme Court justice (1981-2006)

McCreary County v. American Civil Liberties Union, 545 U.S. 844 (2005) (concurring)
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