Here's what Warren Buffett says about the ‘greatest danger’ facing the world

moneywise: Investors often watch the markets and the economy. But in this day and age, you might also want to pay attention to the ongoing war between Russia and Ukraine — because the consequences could be dire.

After Russian officials spoke of using tactical nuclear weapons, U.S. President Joe Biden warned that the risk of nuclear “Armageddon” hasn’t been this high in 60 years.

“We have not faced the prospect of Armageddon since Kennedy and the Cuban Missile Crisis,” he said at a Democratic fundraiser in October.

“He is not joking when he talks about potential use of tactical nuclear weapons or biological and chemical weapons, because his military is, you might say, significantly underperforming,” Biden added, referring to Russian President Vladimir Putin.

“I don’t think there’s any such thing as the ability to easily use tactical nuclear weapons and not end up with Armageddon.”

That’s a scary picture. And what's scarier is that Putin agrees that the risk of nuclear war is increasing. Speaking at a meeting of Russia’s Human Rights Council in December, he didn't rule out the idea of using nuclear weapons first, but said he viewed Russia's nuclear arsenal primarily as a deterrent.

"We have a strategy… namely, as a defense, we consider weapons of mass destruction, nuclear weapons – it is all based around the so-called retaliatory strike,” he said. “That is, when we are struck, we strike in response.”

Still, the possibility of nuclear war makes all other problems seem trivial in comparison.

Legendary investor Warren Buffett once called it “the ultimate problem of mankind.”

‘Only real cloud on the horizon’

Warren Buffett is not a doom-and-gloom type of investor. He’s not shy about expressing his seemingly endless optimism over the U.S. economy.

But if there’s one threat that keeps the investing legend up at night, it’s most certainly the threat of nuclear war.

“It is the ultimate problem of mankind,” Buffett said at his company Berkshire Hathaway’s annual shareholders meeting back in 2006. “And it will happen someday.”

He explained how weapons have evolved through human civilization.

“We've always had people who wish evil on others. Thousands of years ago, if you were psychotic or a religious fanatic or a malcontent, and you wished evil on your neighbor, you picked up a rock and threw it at them, and that was about the damage you could do,” he said.

“We went on to bows and arrows and cannons. But since 1945, the potential for inflicting enormous harm on incredible numbers of people has increased at a geometric pace.”

Buffett expressed similar concerns in 2017.

“I've been concerned since 1945 when the first atomic bomb was used,” he said during a CNBC interview.

“We have developed over these 72 years, since August of 1945, the ability around the world to almost destroy civilization. It's the only real cloud on the horizon.”

What to own in times of crisis

Given this geopolitical crisis and other uncertainties looming in the distance — like an extremely hawkish Fed — it might be tempting to hide out in cash. After all, the stock market has been pummeled in 2022.

Buffett doesn’t exactly believe in stashing your savings under the mattress.

“The one thing you can be quite sure of is if we went into some very major war, the value of money would go down — that's happened in virtually every war that I'm aware of,” he told CNBC in 2014, the last time Russia invaded Ukraine.

“The last thing you'd want to do is hold money during a war.”

Of course, consumers have already learned first-hand the risk of holding money over the past year. With rampant inflation, the purchasing power of your cash savings can deteriorate rapidly.

What should investors own then?

Buffett has always believed in owning productive assets. And his suggestion for times of crisis is no different.

“You might want to own a farm, you might want to own an apartment house, you might want to own securities.”

It’s easy to see the appeal of farmland. Whether boom or bust — or World War III — people still need to eat. These days, it’s also easy to invest in farmland even if you know nothing about farming.

Apartment buildings could be another hedge against inflation and uncertainty.

Sure, real estate has its cycles, but no matter how much economic growth slows down, people need a place to live. And with real estate prices rising to unaffordable levels in many parts of the country, renting has become the only option for many people.

The segment is also becoming increasingly accessible to retail investors.

As for securities, Berkshire discloses its holdings every quarter so you can see which stocks the Oracle of Omaha favors.

According to the latest 13F filing, Buffett’s top five holdings were Apple (AAPL), Bank of America (BAC), Coca-Cola (KO), Chevron (CVX), and American Express (AXP) at the end of Q2.