I’m going to pass along some extended quotes that caught my eye over the weekend.
During the thousand years that included the careers of the Frankish soldier and the Polish king, the Christians of Asia and Africa proved unable to wage successful war with the Moslem conquerors; and in consequence Christianity practically vanished from the two continents; and today nobody can find in them any “social values” whatever, in the sense in which we use the words, so far as the sphere of Mohammedan influence. There are such “social values” today in Europe, America, and Australia only because during those thousand years the Christians of Europe possessed the warlike power to do what the Christians of Asia and Africa had failed to do – that is, to beat back the Moslem invader. — Teddy Roosevelt. 
The Belgian scholar, Henri Pirenne, attempted to explain the reasons for this decline. In his book, “Mohammed and Charlemagne,” Pirenne says it was not the Germanic invasions of the Roman Empire that brought civilization to a halt by the late seventh century. According to Pirenne, “the Germanic invasions destroyed neither the Mediterranean unity of the ancient world , nor what may be regarded as the essential features of the Roman culture as it still existed in the 5th century. …” The destruction, he argued, came from another direction — from Islam, which emerged out of Arabia in the seventh century, stopping European trade in its tracks by suddenly taking control of the Mediterranean. This disruption resulted in near-total economic collapse in the West. “The West was blockaded,” wrote Pirenne, “and forced to live upon its own resources.”
As history records, Western Europe fought back against Islam and eventually recovered control of the Mediterranean.
Looking back on 10 centuries of progress, we need to realize that no law of history guaranteed that Charles Martel would stem the Islamic Juggernaut in 732, stabilizing the defensive position of the West. If the soldiers of the Frankish kingdom had failed at the crucial moment, the West might have ceased to exist. —J.R Nyquist 
The point of my talk — based on my new book, “The Death of the Grown-Up: How America’s Arrested Development Is Bringing Down Western Civilization” — was to explain why perpetual adolescence is not just a cultural drag, but also dangerous to our way of life. I argued that the leveling of adult authority over the past half century or so was accompanied by a leveling of cultural authority. This brought on the age of multiculturalism, a time when Western Civ (like the adult) no longer occupies its old pinnacle atop the hierarchy of cultures. The multiculti conception of equally valuable cultures (except for the West, which is deemed the pits) depends on a strenuous non-judgmentalism. This non-judgmentalism expresses itself in a self-censoring adherence to political correctness. Such non-judgmentalism, such PC self-censorship, is infantilizing because it requires us to suppress our faculties of analysis and judgment.
Case in point: Our society’s refusal to analyze and judge the anti-Western teachings of mainstream Islam for fear of giving offense to the grandees of PC, or to Muslims, or both. This refusal, I maintained, is a brewing civilizational crisis.
Having made ourselves into a self-censoring society, I explained to the students at tea, we now find ourselves confronting an Islamic system that demands such censorship as a point of law. Look what happened to Silvio Berlusconi when, as prime minister of Italy after 9/11, he mounted a heartfelt defense of Western civilization for having enshrined liberty, freedom of conscience, equality before the law and the like — which, he also pointed out, Islam most certainly did not.
The voluble Italian was dumped upon by the world, Western and Islamic. He swiftly recanted to satisfy both the censoring dictates of PC, which outlaws non-Western critiques, and the censoring dictates of Islam, which outlaws criticism of Islam. Berlusconi’s example shows how easily an adolescent, PC society can slip under Islamic law into the hush of dhimmitude.— Diana West