What does “separation of church and state” really mean? Many point out that the phrase is not found anywhere in the Constitution. Rather, it was mentioned by Thomas Jefferson, after the Constitution and the Bill of Rights were adopted. Others note that at the time the Constitution was adopted, about half the states had established state churches and that, although these states on their own ultimately disestablished these churches (ended official state religion), the federal government and federal courts were not involved in this process at all.
The 14th Amendment, not the 1st Amendment, is technically at issue when anyone raises the issue of separating state government operations from religion. Based upon the “Incorporation” principle, after the Civil War and the Reconstruction era, the Supreme Court gradually found various parts of the Bill of Rights to then apply to state governments because the “due process of law” section of the 14th Amendment was deemed to also implicitly include the federal Bill of Rights.
Each state had already incorporated into its own constitution a bill of rights, and often these state constitutional rights were more robust than were the federal Bill of Rights.
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