After Donald Trump secured the Republican nomination on Tuesday night, the BBC rounded up the reactions from the global press to Trump's victory. Aside from some gloating in authoritarian Russia and China, the reaction was pretty shocked.

"The craziest US presidential election campaign begins," Germany's Die Welt daily wrote. "The unthinkable has come to pass."

You've seen similar coverage from the foreign press throughout Trump's rise, the tone of which has been a mixture of panic, terror, and gallows humor.

France's Channel 2 once aired a debate titled, "That Donald Trump could become president of the United States: should we laugh or cry?" In January, the leading German magazine Der Spiegel published an issue titled, "Madness: American Agitator Donald Trump."

It's not just Europe. "Trump seems to be a nightmare for everyone here," Hanin Ghaddar, managing editor of Now, an English news site based in Lebanon, said in March. One of South Korea's largest newspapers, JoongAng Ilbo, declared itself "dumbfounded" that someone with Trump's views could be a "leading candidate in the U.S. presidential race." South Africa's City Press published a piece titled, "God help us all if Trump wins."

Why? Because Trump plays into many countries' worst fears about America.

Part of it is that he embodies the world's worst anti-American stereotypes: vulgar, violent, cash-obsessed, racist. Trump is everything many people hate about the United States, so it's no surprise some are infuriated by his rise.

But it's not just ethos — it's also what he proposes to do to many countries, particularly American allies. Trump's actual foreign policy vision represents a fundamental break with decades of American foreign policy. Given that a lot of American allies depend on those very decades-old policies for their own security, Trump's rise is more than just cartoonish.

For them, it's legitimately terrifying.

Trump is what many foreigners see as the worst parts of America

One of the most insightful things I've read on foreign views of Trump is by German political theorist Yascha Mounk, currently teaching at Harvard.

"If a communist propaganda ministry had commissioned a gifted cartoonist to draw a typically-American rogue, he would have invented a figure like 'The Donald,'" Mounk writes in the German newspaper Frankfurter Allgemeine Zeitung. "A man who embodies the wealthy, boorish philistine, from his self-important attitude to the way his hair is folded this way and that, and someone for whom nothing is sacred — other than money, bosoms, success and power."

Germans, Mounk writes, see Trump as "a symptom of a distinctly American disease":

In no other democracy in the world, it is said, could voters be so openly motivated by greed, show so little concern for less-privileged fellow citizens and be so politically ignorant. Only in hate-filled, under-educated 'Ami-land' could someone like Trump be successful.

Mounk describes Trump as fitting stereotypes of Americans held not just in Germany but in places around the world. A 2005 Pew survey of people in 16 nations found that majorities in most countries described Americans as "greedy" and "violent." A 2005 study in the Journal of Cross-Cultural Psychology looked at data from 48 non-American samples, finding that they described the typical American as (among other things) "arrogant" and "achievement-oriented."

Trump is a man who describes everything he has as "the best," is obsessed with "winning," and tells his followers that the protesters they beat up had it coming. He once literally said, "My whole life I’ve been greedy, greedy for money — but now I want to be greedy for the United States."

Now, most non-Americans don't only see the bad in America — and a lot of the time, these stereotypes are fodder for jokes rather than taken seriously.

But in Trump, they see the bad parts of America swamping the parts of it they admire. That's not just in personality, but also the policies he proposes. Trump's personal qualities would become the ones that define American governance.

"For [some], Trump's mere existence confirms their worst suspicions of the United States," Joyce Karam, the Washington bureau chief for the Arabic daily Al-Hayat, writes. "In a region already predisposed to anti-Americanism, Trump’s Islamophobic and racially charged message is reinforcing long-held suspicions that America is a racist, imperialist nation that wants to exploit and subjugate the Arab world."

The most famous example, of course, is Trump's proposal to ban Muslim immigration.

People around the world condemned it because they thought the idea of discriminating against people based on their religion was reprehensible. It also tapped into a broader international fear about Trump's candidacy: that by accepting Trumpism, America itself would become like him.

"For a putative leader of a nation of immigrants to talk in this way is a watershed moment for the United States," the Guardian, Britain's left-wing daily, wrote in an editorial. "In Mr Trump’s America, the famous words associated with the Statue of Liberty would have to be amended to welcome 'your tired and huddled masses — but no Muslims.'"

But it's also Trump's foreign policies that scare people

But for people in many countries, Trump isn't just a problem because of what he stands for. It's what he actually might do to them once in office that's scary.

Countries around the world depend on a broadly stable global order, which itself depends on a superpower that at the very least doesn't behave erratically.

But Trump has promised everything but stability. His policy proposals include confiscating Syrian and Iraqi oil in areas controlled by ISIS, cozying up with Vladimir Putin, and imposing 45 percent tariffs on Chinese goods that would almost certainly start a trade war. And his entire case for his foreign policy is often premised on the idea that he's unpredictable.

Trump has called NATO "obsolete," and threatened to destroy the alliance unless America's European allies pay the United States in return for the troops America stations on the continent. "Either they pay up, including for past deficiencies, or they have to get out. And if it breaks up NATO, it breaks up NATO," Trump said at a campaign rally.

Nice alliance you've got there — shame if anything were to happen to it, he's telling the world.

He's also suggested that Japan and South Korea should pay for their security alliances with the United States. But there, he went even further, suggesting that these countries should maybe just get their own nuclear weapons so the United States doesn't have to protect them anymore.

These aren't little policy changes. These alliances are literally the foundation of the post–World War II American strategy, supported (in varying forms) by every president and both parties.

The basic idea is that American security alliances around the world deter aggression by hostile powers, like Russia and China, and cement peaceful ties between allies because they're on the same broad side. American alliances create a web of peace around the world, preventing wars between great powers and promoting free global commerce. Everybody wins, at least theoretically.

Trump's point of view threatens to torpedo this system. By telling allies that the US will only support them if they pay up, he's abandoning American promises to defend them. American allies will come to believe that American protection hinges on the whims of an unstable and unpredictable leader.

That is terrifying for people in these countries, who have premised their entire security policies on the existence of American protection. If America won't protect them, might they then be vulnerable to attack? The alliance system, which depends on credible American security guarantees, will start to unravel.

A Trump presidency really would mean a change to America's place in the world

It's hard to overstate how epochal this is. Trump is, without very much thought, threatening to change the fundamental security equation for some of America's closest allies. To take them from protected to vulnerable, with seemingly no appreciation of the consequences.

"This is basically like, 'Hey, maybe we should think about communism,'" Jennifer Lind, a professor at Dartmouth who studies East Asia, said of Trump's comments about Japan and South Korea in March. "With one blasé comment, this entire foundation of US grand strategy is just blasted away."

It's no surprise, then, that the reaction to Trump in the foreign press goes beyond disgust and anger to fear. Trump's foreign policy is all about unpredictable and radical breaks with the status quo — but the world depends on America to be the exact opposite of that.