What we can expect from his foreign policy.

Many Europeans woke up Wednesday morning stunned to learn that while they were sleeping, their nightmare had come true—Donald Trump had won the American presidential election, and not by a small margin.

They had feared this outcome ever since this time four years ago, when Trump lost his bid for reelection, loudly claimed that the race was rigged, and started running again to recapture his throne.

Allied leaders will by and large keep their shudders under wraps. They know—just as the world’s dictators have learned—that Trump is an easy mark for flattery; the best way to deal with him is to praise his wisdom, laugh at his jokes, admire his golf game, and call him “sir” (or, as a Taliban leader once did, to Trump’s pride, “Your Excellency”).

Still, this tactic can go only so far. Trump is who he is. During his single term as president, Trump made clear that he proclaimed his foreign-policy slogan—“America First”—in the same spirit as the isolationists who coined the phrase back in the 1930s, during the rise of Nazi Germany, which they saw as a threat only to people in faraway countries about whom they knew nothing. Trump denounced alliances as a waste of money, openly said he wouldn’t defend any NATO countries that failed to spend as much on their own defense as they’d pledged, and raised doubts about whether he would bother to lift a finger even if they’d met their marks.

In this, Trump will face little internal resistance. At the start of his first term, he appointed establishment national security advisers (he was impressed that they looked straight out of Central Casting) who ended up blocking some of his worst inclinations. This time, he knows the people who share his ideas and will carry out his policies. And with a firm Senate majority, they will easily get confirmed.

During this year’s campaign, he has said he would end the war in Ukraine immediately, even before he takes office—and his one great European friend, Hungarian Prime Minister Viktor Orbán, has revealed that Trump told him his “plan” for doing so is simply to cut off aid to Kyiv. Trump has no love for Ukrainian President Volodymyr Zelensky; it was their 2019 phone call, in which Trump said he’d send anti-tank missiles only if Zelensky released damning material on Hunter Biden, that sparked his first impeachment hearing. Trump has since derided Zelensky as a “salesman” and recently said the U.S. should have never got involved in the war.

As president, Trump scoffed at U.S. defense treaties in Asia. During his bromance with North Korean dictator Kim Jong-il, Trump canceled joint military exercises with South Korea. He also had no enthusiasm about spilling American blood and treasure to defend Japan, either. When a reporter noted that Japan and South Korea might build their own nuclear arsenals if they started doubting the reliability of the U.S. security umbrella, Trump replied that maybe they should. Over the past year, as if on cue, politicians in Seoul and, to some extent, Tokyo have started to talk about that possibility. No doubt the discussions will intensify in the coming days, especially since Trump’s victory comes in the wake of North Korea’s test of a new intercontinental ballistic missile.

Midway through Trump’s term, a second-tier Pentagon official—a Trump appointee—told me that U.S. involvement in a nuclear war was less likely under Trump than it had been under Barack Obama. I asked why he thought so. He replied, “Because a nuclear war would probably start with the U.S. coming to the aid of an ally, and Trump doesn’t give a shit about allies.”

There may be something to this. But if South Korea or Japan built their own atomic weapons, tensions would escalate and an arms race would break out in East Asia. Also, if the U.S. let Putin take over Ukraine, he’d have every reason to believe he could get away with invading the Baltics (a relatively easy task if NATO is removed from the equation) and at the very least intimidating Poland and other former members of Russia’s empire in eastern Europe. Putin’s success in Ukraine would likely embolden Chinese leader Xi Jinping to step up pressure on Taiwan.

In both Europe and Asia, many leaders may respond to pressure from Russia or China by striking deals—to use an old-fashioned word, by “appeasement.” Trump might think that by withdrawing from the world, he can spare the U.S. from war—but war would come anyway, and eventually we would be either pulled in or left stranded in a world that’s hostile to our interests and values.

It’s a good time to check out some history books on the years between World Wars I and II. (E.H. Carr’s The Twenty Years’ Crisis is a good, readable start.) It’s true that history doesn’t often repeat itself, but today, as the saying goes, it certainly is rhyming.

Then there are the wars in the Middle East. For the past year, ever since Hamas’ Oct. 7 attack, President Joe Biden has tried to strike an uneasy balance, upholding (and abundantly supplying) Israel’s right to defend itself while also encouraging Israeli Prime Minister Benjamin Netanyahu (with only infrequent success) to minimize death and damage to Palestinian civilians. Trump has openly said that Israel should finish the war as quickly as possible—not by signing a cease-fire deal (though he wouldn’t necessarily oppose that) but rather by doing whatever Netanyahu thinks he needs to do. This includes razing Gaza, occupying southern Lebanon, even attacking Iran’s nuclear facilities. He and Netanyahu are very tight; neither has done anything to disguise this fact. Trump has even said—and Israeli officials have confirmed—that the two talk on the phone regularly, even though doing so is a violation of the Logan Act and the long-standing idea that the U.S. has just one president at a time.

Netanyahu has never been inclined to make peace without first achieving “total victory” over Hamas in Gaza and over Hezbollah in Lebanon, even though his political opponents and some of his military advisers say this goal is infeasible and, in any case, endangers the remaining Israeli hostages in Gaza. Now that Trump has won the election, the prime minister’s opposition to a deal has only stiffened—and will likely remain so, even if Hamas (which has also rejected every peace offer on the table) suddenly became more pliant (which its leaders might want to consider, given the gloves-off onslaught that is likely to greet them after Jan. 20).

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Iran now also faces a dilemma. Ayatollah Khomeini has said he must strike Israel with a “crushing” blow in response to its missile attack on Iran last month, which turned out to be very damaging to Iran’s military capabilities. The Supreme Leader might want to rethink that declaration as well. First, the Israeli attack—which was a response to Iran’s missile attack on Israel, which was a response to Israel’s assassination of Iranian agents and the leader of Hezbollah, which was a response to … you can trace this thread back for decades—took out most of the air-defense systems guarding Iranian energy, nuclear, and other civil facilities. Even had Kamala Harris won the election, a strong Iranian attack would spur a devastating blow from Israel. (Biden, who pressured Netanyahu to make his recent attack “proportional,” warned Iran that this time, he would not impose any restraints.) But with Trump as president, Netanyahu can elevate his ambitions; Trump might even order the U.S. Air Force to help. (Our planes have the range, and a sufficient supply of bunker-buster bombs, to damage or destroy a lot of Iran’s nuclear facilities.)

Trump may think that Biden made America less secure and the world more violent—and that only he, Trump, can restore peace and order. His self-confidence is about to be severely tested.