Can NATO withstand the Trump-Greenland test?

Secretary general of NATO Mark Rutte and Donald Trump.

The United States’ recent actions under President Trump reveal a brazen disdain for international law and multilateralism. Within days of justifying a military strike on Venezuela — and the capture of President Nicolás Maduro — as a “law enforcement operation”, and following his withdrawal from climate treaties and key UN institutions, Trump has turned northwards, insisting that Greenland — an autonomous territory within the Kingdom of Denmark — can and should be taken by force. This is not reckless and aggressive rhetoric in isolation, but part of a disturbing pattern, marking a deeply unsettling moment for both the North Atlantic Treaty Organisation (NATO) and the post–Second World War international order. It raises an uncomfortable question: Can a security arrangement survive if the alliance’s most powerful member openly entertains territorial ambitions against another member?

Trump’s actions resonate with classical realist assumptions that great powers pursue self-interest in an anarchic system largely unfettered by moral or legal restraint. Greenland’s strategic location and resources thus become objects of power maximisation rather than cooperation. This rejection of liberal constraints accelerates a shift towards a more openly Hobbesian order, recalling Thucydides’ warning that “the strong do what they can and the weak suffer what they must.” From a constructivist perspective, the repeated normalisation of coercive options reshapes norms, making once-unthinkable acts gradually appear plausible.

Trump is not the first US leader to view Greenland through a strategic lens. Since the 1860s — when Secretary of State William Seward floated its acquisition — the island has featured in American security thinking, with US defence responsibilities during the Second World War later formalised through agreements with Denmark and the establishment of bases such as Thule. What distinguishes Trump is escalation. His 2019 attempt to “buy” Greenland revived this dormant ambition, now curdling into a far more dangerous threat of coercion and force.

Greenland’s strategic importance is undeniable. It straddles key Arctic sea lanes, hosts critical early-warning and missile-defence infrastructure, and sits atop vast reserves of rare earths and other minerals, making it a focal point of intensifying great-power competition as melting ice reshapes trade routes and access to resources. While US interest is generally justified as a security imperative to pre-empt rival influence, Trump’s transactional worldview exposes a deeper impulse — one that treats territory, resources, and influence not as subjects of cooperation, but as commodities to be acquired or seized.

The implications of any coercive acquisition of Greenland for the post-War international order would be profound. It would constitute a flagrant violation of Article 2(4) of the UN Charter, shatter Washington’s claim to moral leadership, and risk destabilising the North Atlantic through military confrontation. More dangerously, if a permanent member of the Security Council and principal architect of the post-1945 order openly legitimises territorial acquisition by threat or force, it erodes the core norm restraining revisionism and invites similar conduct by other powers.

Nowhere would the fallout be more damaging — internally or externally — than in NATO. The alliance, the oldest surviving collective security system, rests on shared interests and principles, long presenting itself as a defensive pact committed to peace and international norms. Any explicit or implicit US threat to Greenland, an autonomous territory of NATO member Denmark, undermines these foundations, corrodes trust among its members, and erodes its credibility as a collective security system grounded in respect for sovereignty, territorial integrity, and the rule of international law. Its core promise — that an attack on one is an attack on all — loses meaning if a threat comes from within, prompting smaller allies to hedge or quietly explore alternative security arrangements when their sovereignty appears vulnerable.

NATO has long justified its existence by defending sovereignty and resisting territorial revisionism — principles central to its response to Russia after Crimea and Ukraine. If the alliance tolerates similar impulses within its own ranks, it invites charges of Western hypocrisy. The United States could lose trust, weaken security cooperation with long-standing allies, and may push wavering states towards exploring alternative defence partnerships. China, meanwhile, could exploit such rifts by presenting itself as a “respectful” partner that invests without threatening sovereignty.

NATO’s ability to overcome this crisis depends on whether the episode is dismissed as aberrational rhetoric or recognised as a deeper challenge requiring serious attention. Instead of coercion and threat, the US security concerns, if any, can and must be addressed through cooperation, consent, and deepening defence arrangements with Denmark.

The writer is Dean, Faculty of International Studies, Aligarh Muslim University