Recent weeks have seen escalating threats by Donald Trump to annex Greenland, with growing concern about the potential use of military force against a NATO ally. While Trump may have ruled out using force to annex Greenland for now, Jim Rice argues that its threat has destabilized NATO and placed the US military in the position of being facing potentially unlawful orders to attack allies.

The quote, “history does not repeat itself, but it does rhyme”, widely attributed to Mark Twain, has been used in several contexts with varying degrees of appropriateness. As we approach February 2026 many will recall the 40th anniversary since the 1986 People Power Revolution in the Philippines that overthrew the regime of President Ferdinand Marcos through a opposition and confrontation by a combination of senior military officials, religious leaders and the public. The individuals that took part, confronting the might of the regime, did so with great courage and sacrifice.

Trump backs down after making threats towards Greenland

History’s unlikely and perhaps imperfect rhyme here is that since re-entering the White House in January 2025, President Donald Trump’s increasingly bellicose threats to annex the Danish self governing territory of Greenland have reached the point that by January 2026, the United Kingdom, France, Denmark and Germany had all come to regard the United States military as being a credible security threat. This threat is not only to the NATO alliance, but to the entire rules-based international order. The prospect that long-time NATO allies would ever reach this place of threatening invasion and taking defensive countermeasures in respect to each other would have been unimaginable only a few months ago. However, by January 2026 as Trump’s threat to acquire Greenland “the easy way or the hard way” had escalated, a growing number of core NATO allies have deployed troops in the autonomous region including Denmark, Great Britain, France and Germany.

By January 21st, this tension had broken somewhat as Trump walked back his threats to use force to seize Greenland in a speech at the Word Economic Forum meeting, though reaffirming his desire to acquire the Danish territory. Shortly after this speech and following a meeting with meeting with Mark Rutte, the NATO Secretary General, Trump announced that the US and NATO had “formed the framework of a future deal with respect to Greenland”.

Should Trump’s this deal involve a treaty to supplement or amend the 1951 US-Denmark treaty on Greenland, “The Defense of Greenland Agreement“, such an agreement would require the consent of two-thirds of the US Senate and ratification by the president. This constitutional requirement is found under Article II, Clause 2, Section 2 and may not be accomplished by Executive Order, Trump’s preferred method of governance. Given this constitutional requirement as well as the mercurial nature of this administration, this crisis may have only been temporarily averted.

Greenland, the US and NATO

That Greenland holds strategic importance for the United States and to the Western alliance is not in doubt. The United States has had military bases in the Danish territory since the Second World War, throughout the Cold War up, until the present day. During this time, Denmark and the US have both benefitted from this alliance as have other NATO allies. As former US Navy War College professor, Tom Nichols has recently pointed out, the US and NATO forces defended the sea-lanes in the region including the highly sensitive under sea passages known as the Greenland, Iceland, and the United Kingdom, (the “GIUK” gap).

Yet despite Trump’s claims about the need to annex Greenland due to security concerns about “Chinese and Russian ships,” the reality is that since the Second World War, Denmark has consistently acted in good faith and has agreed to the security accommodations that the US has requested. The Kingdom of Denmark has steadfastly been one of America’s greatest allies in both war and peace. Furthermore, if the security of the region were actually the issue, then isn’t the NATO alliance the best structure to meet those concerns?

It is now apparent that the Trump administration has demonstrated itself to be the party that is acting in bad faith. The most recent negotiations on January 14, 2026, between Vice President Vance, Secretary of State Rubio and the Danish and Greenland Foreign ministers (Lars Løkke Rasmussen and Vivian Motzfeldt) failed to reach any agreement. Given this impasse, there is no mistaking the message that the deployment of Danish and other NATO allied forces sent to the Trump administration. Despite Trump’s apparent ruling out the use of force to take Greenland, after more than 60 years, the United States is now regarded as a security threat and what remains of the NATO alliance is prepared to resist any potential future US invasion with force if necessary.

What do Trump’s threats mean for the US military?

Trump’s rhetoric and possible future adventurism, have not only placed longtime diplomatic and military allies in an impossible position, Trump’s threats also placed the officers and enlisted men and women of the United States military in the position in which they were facing being forced to consider choosing between their orders and their oath to the Constitution. Following the series of boat strikes off the coast of Venezuela which began in September 2025, Senator Mark Kelly along with five other legislators all of whom served in the military or intelligence services released a video clip where they addressed service members and the public, explaining that they are required not to obey unlawful orders.

For his part, combat veteran and former JAG (Judge Advocate General’s Corps) officer, Representative Ted Lieu, has stated unequivocally that any orders directing US service members to take military action against Greenland would be illegal and void:

“If any military member, including the generals on down to enlisted members – if any of them participate in a use of military force against Greenland without congressional authorization, they are following illegal orders. That is simply a fact.”

To put this into a more human context, imagine being a member of the US General Staff, a flag officer who has been issued orders by the Secretary of Defense to attack and seize relevant targets in Greenland with the goal being gaining control over the territory. Such a high-ranking officer would most likely have personal knowledge of those British, Danish, French or German officers. They would likely have served together in field exercises, staff meetings or possibly in combat, in Iraq or Afghanistan. These senior members of staff would be suddenly issued orders to direct lethal force against members of an allied force, and against their comrades in arms. It hardly needs stating that such an order would place an unimaginable burden on the members of the US military.

“World Economic Forum Annual Meeting” by World Economic Forum, CC BY-NC-SA 4.0

One would hope that those experienced members of the United States military would come to the same conclusion as Representative Lieu and would treat the orders as being unlawful. The question then becomes, what would happen next, that is after senior military officers have concluded that to carry out such orders would constitute a criminal act.

Congress has not been completely silent on the issue as Trump’s rhetoric continued. On January 13, 2026, Senators Lisa Murkowski and others introduced the NATO Unity Protection Act, which prohibits using Federal funding “to blockade, occupy, annex or otherwise assert control over the sovereign territory of a NATO member state without that ally’s consent.” Some have suggested that even if the bill were to be passed by Congress, Trump might decide not to heed it.

Lessons from the Philippines’ 1986 “People Power” revolution

The pretext for Trump’s potential actions against Greenland is not founded in legal authority or congressional approval. Instead they have been conceived outside the law at the whim of someone General Mark Milley once referred to as a “wannabe dictator.”

As the Trump administration appeared to be edging toward an illegal annexation, learned and distinguished voices (including Tom Nichols, Anne Applebaum and others) published articles in opposition to Trump’s repeated threats of illegal military aggression in Greenland. However, few (if any) have openly called for his removal from office.

Trump’s back down notwithstanding, does the totality of evidence indicate that things have reached the point where another People Power Revolution is warranted, this time in Greenland and in the United States to deter Trump from embroiling the world in yet another dangerous war and provoking the breakup of the NATO alliance itself?

Senator Kelly, Representative Lieu and their colleagues have urged both officers and enlisted service members not to obey unlawful orders, and if the order to seize Greenland by force is issued, then this call should be heard. Such an order would be in clear violation of Article 2.4 of the United Nations Charter and fundamental norms known as jus cogens. Furthermore, by extension, United States law, through the Constitution’s “supremacy clause” (found in Article VI, Clause 2) designates that signed and ratified treaties are the “supreme Law of the Land.” According to both international and US law then, any order to invade or forcibly annex Greenland would be illegal and, under US military doctrine, an unlawful order.

In February 1986, members of the Philippine military, a group of brave Catholic Sisters and the general population became determined that the time had finally come to bring an end to the dictatorial rule of Ferdinand Marcos. Some 40 years later, should Trump seek to bring about the destruction of the Western Alliance by a foolish and illegal invasion of a longtime ally and friend, then it may be time for Americans to ask themselves, “has Trump gone too far?”

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• Note: This article gives the views of the author, and not the position of USAPP – American Politics and Policy, nor of the London School of Economics.