Even our founding fathers saw the dangers of fanaticism

The atmosphere of our country is unquestionably charged with a threatening cloud of fanaticism, lighter in some parts, denser in others, but too heavy in all. I had no idea, however, that in Pennsylvania, the cradle of toleration and freedom of religion, it could have arisen to the height you describe.

Thomas Jefferson, letter to Thomas Cooper, November 2, 1822
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