As outlandish as it might seem, Trump has sounded serious so far. In a post on Truth Social, Trump said his son, Donald Trump Jr., will be in Greenland this week and added that he will protect the island “from a very vicious outside world.”   

Since December, Greenland quickly rejected Trump, with its prime minister saying that it isn’t for sale and never will be. Denmark, the kingdom under which Greenland exists as an autonomous country, has also pushed back and bolstered its defense on the island. 

Other European leaders have also been worried about the prospect of Trump purchasing Greenland. For instance, French Foreign Minister Jean-Noël Barrot said on Wednesday that Europe will not let another country “attack its sovereign borders” in the context of defending Greenland. 

But it’s tricky to pick a fight when the opponent is as significant as the U.S. and, indeed, Trump himself. Greenlandic people have also expressed a desire for closer relations with the States.

Trump, who made his fortune as a real estate developer, hasn’t backed down. He has emphasized that ownership of Greenland is an “absolute necessity” because of its strategic importance and rich mineral reserves. 

On Tuesday, his ambition turned into a threat when he floated high tariffs (not surprising, given his nickname, “tariff man”) or military coercion against Denmark if his expansionist agenda was interrupted. 

The Panama Canal and Canada are also on Trump’s geographic target list.  

“Every decision President Trump makes is in the best interest of the United States and the American people. That’s why President Trump has called attention to legitimate national security and economic concerns regarding Canada, Greenland, and Panama,” Karoline Leavitt, Trump-Vance Transition’s spokeswoman, told Fortune.

While world leaders and experts have anticipated fresh tariffs under the Trump administration, the president-elect’s bid for Greenland is a problem no one was prepared for. 

“This fetish of Trump’s for the U.S. to buy Greenland poses difficult questions that no one in Europe thought they would have to consider. For Denmark, this is no longer a silly joke which should be rebutted in kind,” Steven Blockmans, an associate senior research fellow at the Centre for European Policy Studies, told Fortune on Wednesday. 

“[Denmark] might find avenues for closer cooperation with the U.S. in negotiating access to critical raw materials; but how much will be enough to satisfy the growing appetite of Mr. Trump?”

The U.S. obsession with Greenland

Trump’s plan may sound bizarre, but this isn’t the first time the president-elect has publicly stated his intentions about the Arctic island. 

During his previous term as U.S. president, Trump floated the idea, which received mixed reactions from his advisors. President Harry Truman also sought to buy the island from Denmark in 1946 for $100 million worth of gold, but the European country declined to sell it, the Wall Street Journal reported in 2019. 

From then to now, a lot has changed geopolitically. Russia has distanced itself from the West and waged war on Ukraine, while China is Trump’s number one target when it comes to tariffs.    

Many factors add to Greenland’s appeal for Trump: It is culturally associated with Europe, sustained via subsidies from Copenhagen, and a member of the North Atlantic Treaty Organization. The island also has a vast U.S. space base, making it the northernmost outpost for the American armed forces.

Perhaps most interestingly, Greenland also houses rare-earth metals that are becoming more accessible because of climate change.   

It’s too early to know how far Trump will go to get his hands on Greenland. But he seems ready to go out on a limb if it means more power, even at the cost of war within NATO and ruffled feathers across Europe.

Update, January 8, 2025: This article has been updated with a comment from the Trump-Vance Transition’s spokesperson.