Stocks were down again on Wednesday, extending a dismal start to the new year for the markets.

More concerns about a slowdown in China weighed on sentiment. So did lingering fears about the growing rift between Saudi Arabia and Iran. Oil prices plummeted as traders worried about what could happen in the Middle East if tensions escalate.

But there was a new thing for investors to fret over as well on Wednesday: North Korea's reported claim that it successfully detonated a hydrogen bomb.

North Korea developing significant nuclear capabilities was not at the top of many investors' lists of things to worry about in 2016. In fact, North Korea didn't even make it on many lists as a threat.

Eurasia Group, which publishes a widely read list of top 10 global geopolitical risks at the start of every year, excluded North Korea entirely.

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The Eurasia list had China and Saudi Arabia on it. ISIS made it as well. So did the possibility of a "Brexit" in Europe.

And there was also a category for "unpredictable leaders." Russia's Vladimir Putin, Turkey's Recep Tayyip Erdogan and Ukraine's Petro Poroshenko were among that group --- but not North Korea's Kim Jong Un.

So will North Korea wind up being this year's so-called black swan? A truly surprising event that turns out to have a huge impact?

Some market experts, including Eurasia Group founder and president Ian Bremmer, said that's unlikely.

"This is a buying opportunity," Bremmer said. "This was planned. Next week, nobody is going to ask me about this. Nobody will care. If Kim Jong Un were in the Middle East, this would be high on our list. But fortunately, he's not."

Bremmer adds that a bigger risk would be if there were signs of cracks in Kim Jong Un's regime. That would lead to more concerns about instability in the region.

Phil Blancato, CEO of Ladenberg Thalmann Asset Management, agreed that investors shouldn't focus much on North Korea.

"There are a number of risks floating around out there. North Korea isn't one. If this was Iran potentially testing the use of a bomb against Israel, the market would be significantly more concerned," Blancato said.

Still, the latest news from North Korea is not helping at a time when investors are already on edge.

"North Korea is something that came out of the blue. It's hard to know how much it is really weighing on the market because of China and oil. But it's adding to the unease," said Bill Stone, chief investment strategist with PNC Asset Management Group.

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Of course, further saber rattling by Kim Jong Un would be bad for Asia -- particularly South Korea.

To that end, South Korea's won currency slipped to its lowest level in months on Wednesday. And shares of big South Korean companies, such as Samsung and Hyundai Motor, both fell more than 2% in trading on Seoul's Korea Exchange.

But the latest nuclear test from Pyongyang (and remember that there have been several over the past few years) shouldn't cause considerable angst for U.S. investors. The slowdown in China -- and what that's doing to commodity prices -- is more worrisome.

"North Korea is more of a political risk than an economic one. That's why China is a much bigger concern than North Korea. We've been worried about China for the past year-and-a-half," said Paul Nolte, portfolio manager for Kingsview Asset Management.

There is also still a lot of skepticism about the validity of North Korea's claims. So the news may be unsettling to investors that are already jittery.

"Yes, this is may be another piece of the puzzle that makes people scared," said Brad McMillan, Chief Investment Officer for Commonwealth Financial Network. "But North Korea? Who cares?"