Breaking bounds

US seizing Greenland would mean sovereignty stops functioning as a hard constraint and becomes a conditional privilege subject to force

For decades, one taboo has helped keep the international system from sliding back toward war: respect for sovereignty. But since President Donald Trump has repeatedly asserted that the United States “absolutely needs Greenland” and refused to rule out the use of military force to obtain it, that norm has come under a stark — and unsettling — challenge.

Since 1945, the modern international order has rested on a deceptively modest bargain: states can disagree about ideology, regimes and alliances, but they must not treat territory as something to be seized by threat or force. That is why the United Nations Charter’s prohibition on the use or threat of force against the territorial integrity of states is often described as the “lowest common denominator” of interstate conduct. It is the norm that makes every form of cooperation — trade, diplomacy, law, and even security coordination — possible.

However, once the strongest actor in the international system signals that territorial integrity can be set aside when “need” is asserted, sovereignty stops functioning as a hard constraint and becomes a conditional privilege — one that holds only until a stronger power decides otherwise.

But sovereignty matters. It is the one principle that partially relieves the anarchic condition of international politics. In a world with no global government, every state must resort to self-help and security is always uncertain.

Respect for sovereignty does not eliminate that uncertainty, but it brings more certainty to what would otherwise be a permanent state of fear. It shrinks the set of worst-case scenarios that policymakers must deal with. If borders are broadly understood to be off-limits to coercion, states can spend less on gaming out territorial emergencies and more on building the economy, improving welfare and developing technologies.

Sovereignty, in other words, functions like a speed limit in a dangerous traffic system: it does not prevent accidents altogether, but it makes normal movement possible without constant panic.

Cynics may argue that even before Greenland, the sovereignty norm had been repeatedly bent or broken, so this time is no different.

In 1999, NATO launched an air campaign against Yugoslavia over Kosovo without an explicit UN Security Council authorization. In 2003, the US and the United Kingdom, leading a coalition, invaded Iraq without Security Council mandate. Not to mention NATO-led operation in Libya in 2011, and the legally contested attacks in Syria in 2014.

What makes the Greenland case stand out is that it dispenses with the usual disguises. In Kosovo, Iraq, Libya and Syria, the actors involved typically argued — however controversially — that they were acting to protect human rights, enforce nonproliferation or fight terrorism. The point is not that those arguments were universally accepted; it is that they were offered — because even the strongest states still felt some need to present the breaching of sovereignty as an exceptional act consistent with a legal or moral purpose.

The rhetoric around Greenland — as well as the way Washington is talking about Venezuela — is strikingly blunt: strategic geography and resource control are treated as sufficient reasons to render military actions (or so-called law enforcement actions) in themselves, with no need for other pretenses. That candor is alarmingly dangerous. Once power no longer even feels compelled to justify its violation of sovereignty, sovereignty is not merely violated — it is treated as irrelevant.

The immediate effect is a shift in what states consider acceptable behavior. When the strongest power signals that raw interest trumps sovereignty, other actors quickly adopt the same mindset. The international system then becomes about how far you can push, how quickly others will accommodate and what costs you can impose before anyone responds. In that environment, restraint is no longer rewarded; it is punished as weakness.

This will have cascading consequences. First, it incentivizes a global arms race and invites nuclear proliferation. If no country can assume its territory is beyond coercion, then the safest strategy becomes building independent deterrent capabilities — more defense spending, more militarization. And given that smaller countries cannot compete with conventional means against great powers, the development of nuclear weapons becomes tempting.

Second, it corrodes multilateralism. Cooperation in an anarchic system depends on the belief that there is a common framework of conduct. When that belief weakens, countries stop treating multilateral agreements as reliable. They hesitate, hold back and look for narrower deals and smaller coalitions instead of broad cooperation. Over time, multilateralism thins out — and the world as we know it becomes less governed by multilateral institutions and more shaped by one-time deals and raw power.

Third, it accelerates the unmaking of globalization. Globalization works when companies can assume borders are stable, contracts are enforceable and shipping lanes and choke points are safe to navigate. If territorial acquisition and coercion become thinkable again, that baseline collapses. Insurance premiums rise; long supply chains look fragile; and risks become hard to calculate. As a result, trade contracts, and cross-border interdependence are discouraged. In the end, globalization dies from thousands of defensive choices made in a world where territory and transit can no longer be taken for granted.

Greenland, is not just a remote island dispute. It is a stress test for whether the post-1945 order can stand. And this is why Denmark’s prime minister warned that a US attack on allied territory would “end everything” — not only NATO, but the entire postwar order.

He Yun is an associate professor at the School of Public Policy at Hunan University. Vasilis Trigkas is an assistant professor of global affairs jointly appointed by Schwarzman College and the School of Social Sciences of Tsinghua University.

The authors contributed this article to China Watch, a think tank powered by China Daily. The views do not necessarily reflect those of China Daily.

Contact the editor at editor@chinawatch.cn.