A Christian majority may be tempted to assume that state support of Christianity would be benevolent because Christianity is true or morally beneficial. History counsels caution. Once government acquires power to define and support “Christianity,” government must determine which Christianity qualifies. It must choose among denominations, doctrines, moral teachings, institutions, and religious authorities. What begins as governmental protection of religion can become governmental supervision of religion. The church may believe it has gained a powerful ally, only to discover that the state has become its regulator.