There is trouble in paradise — but that is nothing new for Guam.

The U.S. island territory in the western Pacific Ocean is ringed by beaches, studded with palm trees and packed with bombs. It's small but strategically significant.

After President Trump threatened to bring "fire and fury" down on North Korea, Pyongyang said Wednesday that it is "carefully examining the operational plan for making an enveloping fire at the areas around Guam."

The declaration might come as a surprise to some mainland Americans, but North Korea has long had a hostile eye turned toward Guam, which is about 2,100 miles away from the Korean Peninsula. The U.S., in turn, has heavily fortified Guam — in part to keep an eye on North Korea.

Guam — only about 30 miles long and 4 miles across at its narrowest point — is located about three-quarters of the way from Hawaii to the Philippines. The isolated island is home to thousands of U.S. troops stationed at Andersen Air Force Base and Naval Base Guam.

The U.S. seized Guam from Spain in 1898 to provide a fueling station for the U.S. fleet in the western Pacific. It quickly became a key part of international communication (the American trans-Pacific telegraph cable passed through Guam) and transportation (it was a fueling stop for trans-Pacific flights).

And it played a crucial role in multiple wars. In World War II, Guam was seized by the Japanese shortly after the Pearl Harbor attacks and won back by the U.S. in 1944. The suffering of Guamanians during the occupation was acknowledged by the U.S. Congress last year, in a bill providing for compensation to survivors.

Then, in the Cold War, the island was a support center. During the Vietnam War, tens of thousands of U.S. soldiers were stationed on Guam.

After the end of the Cold War, the military started to downsize operations. But that didn't last long. At the turn of the millennium, military leaders re-evaluated the importance of keeping forward-deployed forces close to Asia and began sending money, equipment and troops back to the island.

Today, there is a continuous bomber presence. There is an anti-missile unit, focused almost exclusively on North Korea (another anti-missile system has been installed in South Korea).

The U.S. uses the island for war games and joint exercises. Guam also stores a massive quantity of weapons. As of 2014, according to Andersen Air Force Base, Guam held "the largest munitions stockpile in the world" — stored in igloos "deep [in] the jungle, surrounded by brown tree snakes and wild boar."

It may come as no surprise that North Korea sees the military presence on Guam as a provocation.

Bombers "deployed from Guam frequently come flying in the skies over South Korea and explicitly carry out drills for actual war," Pyongyang said in its recent statement, calling Guam "the United States' outpost and starting base for invasion."

"Is the United States indeed the only one with the option of what it calls a preventive war?" North Korea asked, raising the possibility that it would pre-emptively strike Guam.

About 163,000 people live on the island.

Citizens of self-governing Guam are U.S. citizens, although they can't vote for president. The military presence on the island has injected money into Guam's economy and is welcomed, even celebrated, by many residents. But proposals to house even more troops there have raised some concerns about environmental sustainability and cultural identity and colonization, particularly among the indigenous Chamorro population.

As for the specter of a North Korean attack, that is not new for Guam. By 2004 — long before North Korea had missiles that could hypothetically reach the U.S. mainland — South Korean newspapers were reporting that Pyongyang had the capacity to strike Guam. In 2013, Pyongyang started telling the U.S. that it "should not forget" that Andersen Air Force Base, specifically, was within range.

Today, as Pyongyang once again calls Guam out by name, the island's governor, Eddie Baza Calvo, says there is "no threat" to the island.

But Mayor Paul McDonald of Agana Heights, Guam, tells NPR that the threat from North Korea — and the fact that Trump is "fighting back with words" — is being taken very seriously by residents.

"Especially with our elders who have experienced the Second World War, when the Japanese force came and invaded Guam — you know, my mom, she's 91 years old and I was over at the office all day today," McDonald said. "She'd call me every 10 minutes to update her. We are really taking it seriously, a lot of the people in Guam."

The Associated Press reports from Guam's capital, Hagatna:

"While it is extremely unlikely that Pyongyang would risk the assured annihilation of its revered leadership with a pre-emptive attack on U.S. citizens, some residents of Guam are concerned." 'If anything happens, we all got to be ready, be prepared and pray to God that it doesn't happen,' Daisy Mendiola, 56, said after finishing lunch with her family at a restaurant near Hagatna. 'Everyone's afraid, because we're dealing with powers that's beyond us.'"Other residents are worried about the political atmosphere and the government's ability to find a peaceful solution."Todd Thompson, a lawyer who lives on Guam, said he laughed off past threats because he 'figured cooler heads in Washington would prevail, and it was just an idle threat.'" 'But I have to say, I'm not laughing now,' Thompson said. 'My concern is that things have changed in Washington, and who knows what's going to happen?' "Copyright 2017 NPR. To see more, visit