'Popper's paradox' says that tolerant society extending tolerance to the intolerant risk losing their tolerance. The intolerant infiltrate tolerant societies and erode their values.

Paradox of tolerance - Wikipedia (https://en.wikipedia.org/wiki/Paradox_of_tolerance)

It used to work with communism . Then the communists got their noses under the tent.
The US had the good sense to outlaw advocating the overthrow of the government by force.
Smith Act - Wikipedia (https://en.wikipedia.org/wiki/Smith_Act)
Legislation like that was eroded through the courts and viola ;not only is communism tolerated ;it is celebrated . So now we have a commie running the most important city in the world .

Nothing codified in our constitution is more tolerant than freedom of religion. Which brings us to Islam. It is incompatible with every other freedom Americans cherish. It is a Mordred among us sabotaging our culture from within.