The concept of “separation of church and state” isn’t quite as ironclad as you may think.
The First Amendment prohibits laws “respecting an establishment of religion,” a provision that many Americans believe should create a firm wall of separation between church and state. But the Constitution also does not enforce itself. In the United States, we rely on judges and Supreme Court justices to determine what the Constitution means and to apply it to individual cases.
That means that the amount of church and state separation in the United States tends to ebb and flow depending on who sits on the Supreme Court.