WASHINGTON —  If President-elect Donald Trump’s assertion that the United States should have control of Greenland sounds familiar, that’s because he’s said it before — during his first term as president.

Back in 2019, Trump’s call caused a brief diplomatic tiff with Denmark, under whose sovereignty the vast island falls. Then as now, the suggestion was met with derision in some quarters, but it spotlighted serious questions about the icy territory’s strategic significance in an era of accelerating climate change.

Trump’s commentary also pointed up a quandary faced by U.S. allies, which will become more pressing within a few weeks, when the Oval Office changes hands: whether smaller and less powerful states ought to greet startling declarations from Washington with silence, conciliation, throat-clearing obfuscation or clearly stated opposition — especially since the issue in question might simply go away anyway.

Sometimes, Trump ultimately defuses such flaps by saying he was only joking. At other times, he hints that those who defy him might face consequences later. Denmark is a member of the European Union, which is already preparing for a potentially tense relationship with the incoming president.

Here is some background about Greenland, why the president-elect is raising the topic again, and what might come next.

What is this place?

Greenland is an Alaska-sized, self-ruling Danish territory off North America, between the Arctic and Atlantic oceans. It is the world’s biggest island that isn’t a continent, about two-thirds of it lying within the Arctic Circle. It is largely ice-covered and sparsely populated: Fewer than 60,000 people live there. With the exception of foreign nationals, those living there are full citizens of Denmark.

How did this idea even come up?

The president-elect’s unexpected comment came Sunday as he was announcing his choice for U.S. envoy to Copenhagen, PayPal co-founder Ken Howery. In a post on his Truth Social platform, Trump declared that “America feels that the ownership and control of Greenland is an absolute necessity,” citing “purposes of National Security and Freedom throughout the World.”

How did Greenland’s government respond?

Somewhat crisply. On Monday, its elected leader, Prime Minister Mute Egede, said in a statement that Greenland “is not for sale and will never be for sale.” But the prime minister also said Greenland “must continue to be open to cooperation and trade with the whole world, especially our neighbors.”

How did Trump’s 2019 idea play out?

When Trump made his initial real-estate overture, Danish Prime Minister Mette Frederiksen dismissed Trump’s offer as “absurd.” The then-president termed that response “nasty” and called off a planned state visit to Denmark.

Still, the idea of such a purchase was not unprecedented. The United States had made several similar forays, dating to the 1860s, all of them short-lived.

This time around, any headaches for Denmark could be longer-lasting. Trump was already 19 months into his first term when he floated the purchase notion. With his swearing-in still four weeks away, there will be a full four years for the issue to simmer.

Is territorial expansion a theme for Trump’s second presidency?

In this postelection, pre-inauguration phase, Trump has already made waves by musing about the status of Canada, suggesting, in an apparent jab at Prime Minister Justin Trudeau, that the United States’ sovereign northern neighbor could become a 51st state. Also over the weekend, he hinted that Washington could move to seize control of the Panama Canal, ceded back to Panama a quarter of a century ago, over what Trump termed excessive fees to transit the vital waterway.

There has been no indication the president-elect intends to follow up on any of these territorial propositions, or what would be the mechanism for doing so.

Why is Greenland strategically significant?

The island is home to a large U.S. military base. The melting of Greenland’s ice sheet, documented for years and known to be speeding up, could lead to the opening of previously blocked international shipping passages, spurring great-power competition in the Arctic. In addition, Greenland possesses immense mineral riches — gold, silver, copper and uranium — whose potential extraction would be complicated by harsh weather and lack of road access, as well as environmental concerns.

President-elect Trump dished out a fiery Christmas message on Wednesday in which he wished a “Merry Christmas” to “Radical Left Lunatics,” told the 37 prisoners whose death row sentences were recently commuted by President Biden to “GO TO HELL!,” and more.

“Merry Christmas to the Radical Left Lunatics, who are constantly trying to obstruct our Court System and our Elections, and are always going after the Great Citizens and Patriots of the United States but, in particular, their Political Opponent, ME. They know that their only chance of survival is getting pardons from a man who has absolutely no idea what he is doing,” Trump declared on Truth Social.

“Also, to the 37 most violent criminals, who killed, raped, and plundered like virtually no one before them, but were just given, incredibly, a pardon by Sleepy Joe Biden. I refuse to wish a Merry Christmas to those lucky “souls” but, instead, will say, GO TO HELL! We had the Greatest Election in the History of our Country, a bright light is now shining over the U.S.A. and, in 26 days, we will, MAKE AMERICA GREAT AGAIN. MERRY CHRISTMAS!” he added.

TRUMP AND BIDEN OFFER CHRISTMAS GREETINGS AS US APPROACHES TRANSFER OF POWER

Biden recently announced that he commuted the sentences of 37 prisoners on federal death row to life sentences without the potential for parole.

“Make no mistake: I condemn these murderers, grieve for the victims of their despicable acts, and ache for all the families who have suffered unimaginable and irreparable loss,” the president said in a statement, but noted that he is “more convinced than ever that we must stop the use of the death penalty at the federal level.” 

TRUMP PLEDGES TO BRING BACK FEDERAL EXECUTIONS AFTER BIDEN COMMUTES DEATH SENTENCES FOR 37 INMATES 

President Joe Biden speaks at the US Department of Labor in Washington, D.C., on Monday, Dec. 16, 2024. (Samuel Corum/Sipa/Bloomberg via Getty Images)

In a separate post, Trump declared, “Merry Christmas to all, including to the wonderful soldiers of China, who are lovingly, but illegally, operating the Panama Canal (where we lost 38,000 people in its building 110 years ago), always making certain that the United States puts in Billions of Dollars in ‘repair’ money, but will have absolutely nothing to say about ‘anything.’

He also discussed Canada, referring to Prime Minister Justin Trudeau as the “Governor” of America’s northern neighbor, while suggesting that Canadian businesses would boom if the nation became a U.S. state.

TRUMP FLOATS NHL LEGEND WAYNE GRETZKY AS CANADIAN PRIME MINISTER AMID TRUDEAU TURMOIL

Justin Trudeuau, prime minister of Canada, and Joe Biden, president of the United States, talk as part of the G20 Summit Rio de Janeiro 2024 at Museu de Arte Moderna on Nov. 19, 2024 in Rio de Janeiro, Brazil. (Wagner Meier/Getty Images)

“Also, to Governor Justin Trudeau of Canada, whose Citizens’ Taxes are far too high, but if Canada was to become our 51st State, their Taxes would be cut by more than 60%, their businesses would immediately double in size, and they would be militarily protected like no other Country anywhere in the World. Likewise, to the people of Greenland, which is needed by the United States for National Security purposes and, who want the U.S. to be there, and we will!” Trump declared.

With Donald Trump set to return to the White House next year, there’s much speculation on how his second administration will affect press freedom. The short answer is that we don’t know, but prognosticators do have the benefit of an important dataset: his first term.

And, if that record is any indication, national security “leaks” to the press may be an area of tension between journalists and the new leadership at the Justice Department. If there is a chilling effect on sources coming forward with newsworthy information in the public interest, Americans will be less informed and the American government will be held less accountable.

Things have been quiet on that front for the last four years, but the first Trump administration inherited and expanded the Obama administration’s aggressive pursuit of sources who disclosed government secrets to the press.

And President-elect Trump has often decried national security leaks and called for aggressively investigating and prosecuting them.

It would be foolish for press advocates to discount the possibility of a repeat of his first term, and perhaps an escalation.

There are several federal laws that can be read to criminalize the public disclosure of national security secrets. The most prominent is the Espionage Act of 1917, a World War I-era law that was initially used against domestic opponents of the war but applies to the act of communicating, delivering or transmitting “information relating to the national defense,” a broad term, to anyone not entitled to receive it.

In other words, if someone were to anonymously slip a manila envelope under a reporter’s door with government secrets — even secrets that the public has a clear interest in knowing, such as the warrantless domestic wiretapping by the George W. Bush administration — the Justice Department has consistently claimed the authority to investigate and prosecute the source, as well as the journalist, under the Espionage Act. There is no “public interest” defense.

Historically, it hasn’t been used that way. For about 90 years, the Espionage Act was deployed against actual spies, not journalists’ sources. There are a few exceptions — most prominently the Pentagon Papers case, in which the government launched a failed prosecution against Daniel Ellsberg and Anthony Russo — but source cases are in the single digits. And, while there were investigations involving journalists, no reporter or news outlet was ultimately prosecuted under the Espionage Act in that period.

The reason is simple. When the reporting is in the public interest, taking the leaker or journalist to court would be a “political firestorm,” as a federal appeals court judge put it in one of those few exceptions, a 1980s case involving a leak of classified photographs.

But the Bush and Obama administrations marked a shift in practice.

Under President George W. Bush, the Justice Department brought the first Espionage Act case other than Russo against individuals outside government, who had not sworn to protect government secrets. The Bush administration also featured the Valerie Plame case, which started as a leak investigation, in which Judith Miller of the New York Times spent 85 days in jail for refusing to identify a confidential source from her reporting about the run-up to the Iraq war. And the Bush Justice Department issued a subpoena in 2008 to force the New York Times’ James Risen to identify his source in another leak case, which the Obama administration pursued until 2015.

Then the Obama administration started to bring Espionage Act prosecutions against journalists’ sources in earnest. Depending on how you count, his administration brought 10 such cases. That is more than all other presidents combined.

Trump’s first term followed that trend. The Justice Department brought eight cases against journalist sources, including two under bank secrecy laws, as well as the Julian Assange case. The Assange case is complicated, but he was charged in part under the novel and dangerous legal theory that publishing secrets is a crime.

These cases can involve secret government demands for reporters’ notes; phone, email and text records; and correspondence with sources. That kind of snooping can reveal the constellation of a journalist’s sources beyond just the investigation in question and can give the government visibility into other stories the newsroom is investigating, including stories about the government. As Miller said when facing jail time: “If journalists cannot be trusted to keep confidences, then journalists cannot function and there cannot be a free press.”

The Justice Department during Trump’s first term turbocharged Obama-era approaches. In addition to seizing years of records from reporter Ali Watkins’ phone and email providers, a Customs and Border Protection agent threatened to reveal private information unless she identified her sources. Watkins was a reporter at Politico at the time of the questioning and was at the New York Times when she learned of the records seizure.

Then, in the early days of the Biden administration, we learned that the Justice Department in the last days of the Trump administration had authorized demands for phone and email records for eight reporters at CNN, the New York Times and the Washington Post in three separate leak investigations. It did so without notifying those outlets in advance — to give them a chance to negotiate or challenge the demands — and the CNN and New York Times demands came with a gag order preventing newsroom lawyers from even alerting the reporters that they had been targeted.

The history of leak investigations under Presidents Bush, Obama and Trump shows that the threat to the free flow of information is bipartisan and spans administrations. President Biden’s term has been a notable exception, but a reprise may be coming.

Gabe Rottman is the policy director of the Reporters Committee for Freedom of the Press.