For the Left, tolerance does not mean tolerance. It means first, acceptance. And second, celebration. That is totalitarianism: You not only have to live with what you may differ with, dear citizen, you have to celebrate it or pay a steep price.
America will nurture a new Muslim - one who can believe in Muhammad and the Quran but who abandons belief in a Shariah-based state and affirms the primary American value of individual liberty, which has not been a normative Islamic value.
Every age has found some alternative to American values appealing. The number of Western intellectuals enamored of fascism and all the various expressions of Marxism was legion.
Leftism has influenced the literary, academic, media, and, therefore, the political elite far more than any other religion. It has taken over Western schools from elementary through graduate.