See inside Greenland's sole US military base, the only place JD Vance is set to visit amid Trump's territorial ambitions

Trump first expressed interest in buying Greenland, the world's largest island and an autonomous Danish territory, during his first presidency. In addition to being rich in natural resources, Greenland's Arctic location is well-placed to further US interests by countering China and Russia.

Since his reelection, Trump has repeatedly conveyed his desire to acquire Greenland and said he would not rule out the use of military force to take it.

"We need Greenland for national security. One way or the other we're going to get it," he said in his joint address to Congress in March.

Both Denmark and Greenland's leaders have maintained that the island is not for sale.

Second lady Usha Vance was originally scheduled to visit Greenland on a solo trip from Thursday through Saturday to "visit historical sites, learn about Greenlandic heritage, and attend the Avannaata Qimussersua, Greenland's national dogsled race," the White House said.

Instead, the trip has been scaled back. The vice president and second lady are scheduled to visit Pituffik Space Base in Greenland, the US military's northernmost installation, on Friday.

Usha Vance's solo trip could have violated diplomatic protocol by sending a delegation to another country without an invitation. The amended plan — visiting a US base — avoids that potential violation. While Trump said on Monday that "people from Greenland are asking us to go there," the government of Greenland said they had not invited any foreign delegations to visit.

"Just for the record, Naalakkersuisut, the government of Greenland, has not extended any invitations for any visits, neither private nor official," the government's official Facebook page wrote in a post on Monday.

Greenland Prime Minister Múte Bourup Egede also called Usha Vance's planned trip "very aggressive" in an interview with Sermitsiaq, a Greenlandic newspaper.

The White House did not immediately respond to a request for comment.

While the US doesn't own Greenland, it has had a military presence there since World War II.

Pituffik Space Base, originally named Thule Air Base, was formally established in 1951 as part of a Cold War-era defense treaty between the US and Denmark. It is located in Pituffik, Greenland, 750 miles north of the Arctic Circle and halfway between New York and Moscow.

As a Danish territory, Greenland does not have a military of its own.

As the Pentagon's northernmost military base, Pituffik Space Base acts as a key Arctic defense outpost. Because of its location on the "top of the world," it is an optimal vantage point for monitoring missile launches by US adversaries like Russia and establishing space superiority.

The base is the site of a phased-array radar, which can detect sea-launched and intercontinental ballistic missiles, and a surface-to-air missile system, which intercepts hostile threats.

The base has a Satellite Command and Control system to maintain real-time communications and data relay with military and intelligence satellites. Its high-altitude location also allows it to more frequently track polar-orbit satellites, which can monitor the entire Earth's surface over time as the planet rotates below them.

Because Pituffik's primary mission is space surveillance and missile warning, the space base doesn't house a permanently stationed fighter wing or naval fleet.

Instead, it acts as a strategic logistics and defense hub for Arctic missions and under-ice operations. From the site, which is the world's northernmost deep-water seaport, surface vessels and submarines operated by the US Navy and allied forces conduct Arctic patrols and cold-weather training exercises.

Aircraft regularly fly in and out of the former air base, such as military cargo and refueling planes and maritime patrol aircraft. Occasionally, fighter jets and long-range bombers will fly to the base for Arctic deterrence deployments and training flights.

While it doesn't have a permanent combat force, the Air Force does have one tugboat at Pituffik to support port operations, icebreaking, and maneuvering ships.

A small but significant asset, the Rising Star helps keep supply routes open by breaking up and pushing floating ice. The tugboat guides supply ships through the port, making it a critical component in bringing fuel, food, and equipment to personnel year-round.

However, since the base is locked in by ice for nine months of the year, the Rising Star gets limited use because it can only be operated when the port is completely ice-free.

Pituffik Space Base is surrounded by ice for nine months out of every year. The closest town, the Inuit village of Qaanaaq, is located 65 miles away.

Temperatures can range from 60 degrees Fahrenheit in the summer, when there are 24 hours of daylight, to -50 degrees Fahrenheit in the winter, when there is no sunlight for weeks.

Winter storms are categorized into five levels from least to most severe: Normal, Alpha, Bravo, Charlie, and Delta. At the Bravo level, the buddy system is implemented so that no one walks outside alone. Non-essential facilities close at the Charlie level, and personnel must shelter in place during Delta storms.

About 150 personnel are stationed at Pituffik.

The Dundas Buffet Dining Hall on base serves three meals a day with payments accepted through a meal card.

The Base Exchange, also known as "BX," sells groceries, toiletries, souvenirs, and other assorted goods. It also houses a barber shop.

There are no ATMs at Pituffik Space Base, but the Base Exchange accepts debit and credit cards as well as US dollars.

Pituffik Space Base features a bowling alley, a chapel, and a community center with a theater and craft room.

There's also a gymnasium and workout room stocked with weights and treadmills.

Pituffik Space Base's official Facebook page shows personnel participating in recreational events such as a Hawaiian-themed Arctic luau party, Greenlandic Heritage Week, and cross-country skiing.

The US built airbases and weather stations across the ice sheet during World War II as refueling stops on transatlantic flights and supply routes.

Two decommissioned airbases are now being used as civilian airports, and a third was abandoned after the war ended.

During the Cold War, the US Air Force also built four stations on Greenland's coasts as part of a larger communication network of more than 60 radar installations to detect Soviet bombers. Most of the stations have since been deactivated, left to deteriorate atop Greenland's ice sheet.

Late last year, NASA scientists detected an underground base for a top-secret Cold War-era missile operation known as Camp Century. Now buried 100 feet under the ice, the abandoned network of subterranean tunnels once operated under the guise of an Arctic research facility before the US government declassified it in 1995.

But the abandoned military sites represent more than just relics of past global conflicts. Thousands of gallons of biological, chemical, and radioactive waste left behind on the bases pose a significant environmental threat, especially as the planet warms.

The US military failed to clean up decommissioned facilities like Camp Century, assuming the ice sheet would entomb the waste and infrastructure over the years.

However, at the current melting rate of the Arctic, researchers estimate that the waste could resurface around 2100. The question remains as to who is responsible for cleaning up the waste from abandoned US military facilities scattered throughout Greenland.

The US has long pursued access to or control over Greenland due to its strategic and economic significance, dating back as early as the late 19th century.

Since his return to the White House, Trump has continued to double down on his ambitions to secure the self-governing territory within the Kingdom of Denmark, saying he won't rule out military force or economic coercion to do so.

Though the Danish government has remained steadfast in refusing the sale, Trump's so-called "real estate deal" has spotlighted Greenland's growing desire for independence from Denmark and disinterest in being owned by anybody, including the US.

"Greenland is for the Greenlandic people," Greenland Prime Minister Egede said at a January news conference. "We do not want to be Danish. We do not want to be American. We want to be Greenlandic."