Leftists are so far gone that they are willing to protract their nihilism unto the destruction of the very secular values that they supposedly champion. Pascal Bruckner:
Generations of leftists saw the working class as the messianic leaven of a radiant humanity; now, willing to flirt with the most obscurantist bigotry and to betray their own principles, they [have] transferred their hopes to the Islamists.
The Muslim as the new proletarian.
The worst of the great religions, "the saddest and poorest form of theism," (Schopenhauer) is defended when a defining project of the Left was the cleansing of the earth of the "opium of the people." (Karl Marx, full quotation here.)
Add to that the absurdity that the Left, whose own secular values are secularizations of Christian notions, attacks Christianity viciously while cozying up to Islamists.
It's insane, but then the Left is insane in any case.