“A little learning is a dangerous thing,” wrote the poet Alexander Pope. Three centuries later, Pope’s aphorism perfectly — and dangerously — describes President Trump’s understanding of history as a zero-sum clash of civilizations in which “the West” can triumph by imposing its will.

The speech Trump delivered Thursday in Warsaw’s Krasinski Square might have been appropriate when Britannia ruled the waves and Europe’s great powers held dominion over “lesser” peoples around the globe. It had nothing useful to say about today’s interconnected world in which goods, people and ideas have contempt for borders.

“The fundamental question of our time is whether the West has the will to survive,” the president said. “Do we have the confidence in our values to defend them at any cost? Do we have enough respect for our citizens to protect our borders? Do we have the desire and the courage to preserve our civilization in the face of those who would subvert and destroy it?”

Trump added what he probably thought of as a Churchillian flourish: “I declare today for the world to hear that the West will never, ever be broken. Our values will prevail. Our people will thrive. And our civilization will triumph.”

Triumph over whom? Trump mentioned “radical Islamic terrorism” as one of the enemies posing “dire threats to our security and to our way of life,” but he didn’t stop there. He went on to add Russia and — weirdly — “the steady creep of government bureaucracy” to the list. It is appalling that the president would describe patriotic public servants as a kind of fifth column that “drains the vitality and wealth of the people,” and I guess some precious bodily fluids as well.

But what does Trump mean when he speaks of “the West” and its civilization? “Americans, Poles and the nations of Europe value individual freedom and sovereignty,” he said. “We must work together to confront forces, whether they come from inside or out, from the South or the East, that threaten over time to undermine these values and to erase the bonds of culture, faith and tradition that make us who we are. . . . We write symphonies. We pursue innovation. We celebrate our ancient heroes, embrace our timeless traditions and customs, and always seek to explore and discover brand-new frontiers.”

That’s what I mean about a little learning. If the president read a few history books, he’d know that for most of the past 2,000 years, China and India were the world’s leading economic powers and Europe was a relatively primitive backwater. He’d know that Europe rose to dominance not by erecting walls but by opening itself to the rest of the world — its resources, products and people.

There is nothing pure about Western civilization. Its ability to absorb and incorporate outside influences has proved a great strength, not a weakness. Imagine Italy without tomato sauce, a gift from the New World — or the United States without the high-tech companies founded by immigrants, gifts from the Old.

Of course Trump is right to call for a united front against terrorism. But the solution, in a globalized world, cannot be to hunker behind walls, however big and beautiful those walls might be. Industrial supply chains cross borders and span oceans. Words and images flash around the globe at the speed of light. Global issues, such as nuclear proliferation and climate change, demand global solutions. Like it or not, we are all in this together.

The correct response to the terrorism threat, which is real, is to isolate it as an abomination that is as much a grievous insult to Islam as to any other faith — and that has taken the lives of far more Muslims than non-Muslims. The wrong response is to posit that “the West” is besieged by, and therefore at war with, a hostile civilization. That’s a fight in which everyone loses.

Trump did finally make clear that the United States remains fully committed to Article 5 of the NATO treaty, which states that an attack on one member of the alliance is tantamount to an attack on all. He was tougher on Russia than in the past, and he cited “propaganda, financial crimes and cyberwarfare” as “new forms of aggression” that must be countered.

But viewing the fight against terrorism as some kind of civilizational Armageddon is wrong. Trump seems to view himself as the West’s defender against 1.6 billion Muslims, almost all of whom want only to live in peace. We need a capable president, not a crusader in chief.

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