On various occasions and beginning decades before he was elected president, Ronald Reagan warned that "freedom is never more than one generation from extinction." He understood, and he wanted others to understand, that liberty is not an entitlement. It's a rare and precious commodity that "must be fought for."
In Europe last week, President Trump raised this issue again but he broadened it and framed it more pessimistically. "The fundamental question of our time," he said, "is whether the West has the will to survive."
Reactions from those who call themselves progressives ranged from the ignorant to the deranged. Jeet Heer of the New Republic, Jonathan Capehart of The Washington Post, Jamelle Bouie of Slate, Amanda Marcotte of Salon and Sarah Wildman of Vox — all accused Mr. Trump of harboring "white nationalist" and "alt-right" views and blowing "dog whistles."
Peter Beinart, who teaches journalism and political science at the City University of New York, went further. He called Mr. Trump's concern for the survival of Western civilization "perhaps the most shocking sentence in any presidential speech delivered on foreign soil in my lifetime."
He objected to the president even making reference to "the West" because, he asserted in the Atlantic, it is a "racial and religious term." To be "considered Western," he added, "a country must be largely Christian (preferably Protestant or Catholic) and largely white."
This is claptrap of the highest order. First, because Mr. Trump was obviously using "the West" to mean what, in a more confident era, we called the Free World. Second, because the West — a term also used to indicate the developed world, the modern world, the non-communist world, NATO and the secular world — includes the most diverse populations on the planet.
This truth should be held self-evident: Freedom, human, civil and individual rights, representative government, separation of church and state, the rule of law, pluralism and tolerance are all Western concepts, rooted in classical Greece and Rome and developed in the Enlightenment. The American Revolution began a historic attempt to build a nation-state based on them.
Non-Westerners may embrace such values. Millions of people from non-Western lands prefer to live in what Mr. Trump called "the Western community of nations" and willingly risk their lives to defend their adopted homes. By contrast, how many American and European progressives are applying for citizenship in Venezuela, Sudan, Pakistan and other non-Western countries?
What about the legacy of slavery, imperialism and colonialism? What about racism, sexism and homophobia?
Anyone with even the most cursory grasp of world history — meaning anyone who didn't spend his/her/their college years chanting "Hey, hey, ho, ho — Western Civ has got to go!" — would know that these practices are not peculiar to the West. On the contrary, they were the norm in virtually every corner of the world from time immemorial.
It required a revolution in moral thinking to come to the conclusion that slavery, bigotry and discrimination are evils. That revolution began within the West and was led by such individuals as William Wilberforce who — trigger warning — was a white, evangelical Christian.
Slavery was abolished in Saudi Arabia only in 1962 and influential clerics in that land continue to object to the prohibition. The last nation to formally abolish slavery was the Islamic Republic of Mauritania in 1981. The jihadis of Boko Haram and the Islamic State revive the slave trade where and when they can.
Democracies not geographically Western have borrowed Western institutions, practices and beliefs. Some of the freest non-Western countries today were once colonies of the West or defeated by the West in war.
But the fall of the Berlin Wall did not transform Russia into a free country. Mustafa Kemal Ataturk intended for Turkey to join the West but Turkey's current leader, Recep Tayyip Erdogan, is taking his society in a different direction. I believe many Iranians today — having suffered under Shia Islamism for nearly two generations — would embrace Western values if they had the chance, but that proposition can't be tested so long as the mullahs have the guns.
Western liberal democracy has rivals and enemies. It took a world war to stop the march of Nazism, a totalitarian ideology based on racial supremacy. It took a Cold War to stop the spread of communism, a totalitarian ideology based on class supremacy. Today, Islamism, a totalitarian ideology based on religious supremacy, threatens free peoples and those who might like to be. We don't know what it will take to defeat Islamism. We don't even know that it will be defeated.
Islamists regard Islamic imperialism not as a stain on their history but as a glorious legacy. They are inspired by that fact that, in 1453, the Ottoman sultan, Mehmed II, conquered the Christian capital of Constantinople, which was soon transformed into the capital of a great and growing Islamic empire and caliphate, one that would endure for centuries.
How encouraging it must be for Islamists to hear Mr. Beinart and other progressive chatterers call the West a bastion of racial and religious oppression, a civilization not worth defending. And one can only imagine what they think when those under the influence of progressives display anti-Western animus. Consider Kathy Griffin, the actress who thought it would be amusing to identify with jihadis by posing for a picture holding what appeared to be the severed and bloody head of Mr. Trump.
"Our own fight for the West does not begin on the battlefield," the president added last week. "It begins with our minds, our wills, and our souls." Yes, it does, and that, I'm afraid is the nub of the problem.