Conquest Is Back

The norm against territorial conquest is a pillar of the post-1945 international order, but that pillar is now crumbling. Russia’s invasion of Ukraine in 2022 is certainly the most egregious recent violation of this prohibition—an outlier, as an attempt to capture an entire sovereign country. Yet if Moscow gets to walk away with pieces of Ukrainian territory, and particularly if that transfer wins international recognition, other powers may be more tempted to wage wars of conquest.

States have never consistently complied with the rule, enshrined in the UN Charter in response to Nazi Germany’s swallowing other countries whole during World War II, that proscribed the forcible seizure of another state’s territory. But it was broadly observed until fairly recently. Argentina was swiftly ejected from the Falkland Islands after its invasion in 1982 by the combined force of the British military and a UN Security Council resolution. After Iraq invaded Kuwait in 1990, a U.S.-led and UN-approved coalition stepped in to restore Kuwait’s sovereignty. When Russia attacked Crimea in 2014, however, outside powers failed to fully enforce the norm. Many countries protested, but Crimea’s transfer to Russia has become a de facto reality. And this time, after Russia’s full-scale invasion, the world’s increasingly mixed reaction to such a blatant assault has clearly signaled the degrading strength of the norm.

Norms die slowly. Attempted land grabs as big and brazen as Russia’s in 2022 are likely to remain rare, at least for now. But as aggressors go more or less unpunished, states may increasingly act on territorial claims in murky jurisdictions—those least likely to trigger a significant international response. These small-scale attacks may prove most damaging to the norm against territorial conquest. As violence ticks up, the larger web of rules and institutions that make up the international system could begin to come undone. Although far from inevitable, the norm’s demise would leave the world in dangerous terrain.

HEALTH CHECK

Judge the health of a norm in international relations by the actions and statements of countries responding to violations. Immediately after Russia’s incursion in February 2022, many countries spoke out in defense of the prohibition against territorial conquest. But that outrage has become more muted in the years since. Although the European Union, the United States, and their allies have applied forceful and consistent sanctions on Russia, many countries have maintained normal relations with Moscow. Under the Trump administration, Washington’s continued participation in the sanctions regime is now in doubt.

On Russia’s war in Ukraine, the court of global public opinion is increasingly mixed. European populations are generally supportive of Ukraine’s resistance to the Russian invasion—the fear that Russia could target other European countries next gives them a clear interest in preserving the norm against territorial conquest. But even in Europe, support for fighting until Ukraine’s losses are fully reversed may be waning. And in the United States, where President Donald Trump has signaled that he is less committed to Ukraine’s survival than his predecessor, Joe Biden, concerns about Ukraine in particular and preserving norms about sovereignty in general are not as salient as they are in Europe. Recent polling shows increasing support, especially among Republicans, for ending the war in Ukraine even if doing so means Ukraine must cede territory to Russia.

Many outside the West were horrified by Russia’s 2022 invasion. Martin Kimani, then Kenya’s ambassador to the UN, spoke at a UN Security Council session a few days before Russia’s February 2022 invasion and condemned “irredentism and expansionism” and the wilting of international norms “under the relentless assault of the powerful.” But many commentators in the global South have also criticized Europe and the United States for taking a selective approach to norm enforcement; many Western countries that have pushed back against Russia’s assault on Ukraine have violated state sovereignty themselves in the not-so-distant past, such as in the U.S. invasion of Iraq in 2003, or ignored other violations of international law, such as in their support for Israel’s war in Gaza. Inconsistent responses to various breaches of sovereignty—beyond just territorial conquest—can undermine all of these interrelated norms. Norms lose their potency, after all, when they do not keep powerful states from doing what they want.

Still, the fact that states feel obliged to invoke the norm against territorial conquest even as they violate it indicates that there is life in the norm yet. Russian President Vladimir Putin argued that Ukraine was not a real state, which would mean the prohibition would not apply. Beijing, similarly, claims that Taiwan has always been part of China, and Israel does not recognize Palestinian statehood. Rwandan President Paul Kagame has used the M23 rebel group as a front to make territorial incursions in the Democratic Republic of the Congo while insisting that Rwanda is not involved in the conflict and that its interests are purely defensive. Venezuela’s 2023 referendum on taking Guyanese territory invoked decades-old international agreements to support its claim while ignoring other, more recent rulings by the International Court of Justice that rejected it. Even Trump’s statements about the United States buying Greenland, renegotiating rights to the Panama Canal, seizing Gaza to develop it, and making Canada the 51st state seem to favor transactional arrangements over coercion. But Trump’s refusal to rule out the use of force, and the United States’ refusal to name Russia as the aggressor in Ukraine in a recent G-7 resolution and in UN votes, are worrying steps in the wrong direction. If and when states stop invoking the norm against territorial conquest or rationalizing their actions in ways that indicate at least a shallow allegiance to it, the norm will have died. Bolder and more frequent territorial aggression could follow.

DEATH BY A THOUSAND CUTS

Nibbling around the edges of countries may be more damaging to the norm against territorial conquest than trying to swallow them in a single bite. Compare the global response to Russia’s 2014 invasion of Crimea with the response to its full-scale attack in 2022. Both clearly violated the norm. In 2014, the world’s reaction was relatively weak: the seizure was condemned in principle, but apart from sanctions there was little material pushback against Russia, and even today few expect a settlement to return Crimea to Ukraine. By normalizing limited, if still brazen, territorial conquests, the halfhearted response may have paved the way for Moscow’s invasion in 2022. In this case, the world reacted more strongly precisely because Russia’s claims extended to an entire state—a glaring, indisputable violation of the norm. Now consider a counterfactual scenario, in which Russia attacked only the Donbas region of Ukraine in 2022. The outcome, in terms of territorial control, might not have been much different from the likely outcome of the full-scale war, with Russia ending up with the Donbas and Ukraine surviving in truncated form. But Moscow’s smaller-scale land grab probably would not have triggered as vigorous an international response. If norms are only as strong as the world’s reaction to a transgression, a more limited Russian invasion would have set the norm against conquest on a more certain, if slower, path of erosion.

Even so, any transfer of Ukrainian territory to Russia will further normalize territorial conquest. The harm could be minimized if the transfer were unofficial, with a frozen conflict giving eastern Ukraine a status similar to that of Abkhazia and South Ossetia—territories that Russia controls but most of the world considers to be part of Georgia. Just as likely, however, is a transfer of territory that comes with at least some international recognition. An agreement between the United States and Russia that sidelines Ukraine, or even a European-brokered truce that includes a promise of security guarantees for what remains of independent Ukraine, could effectively legitimize the division of Ukrainian territory. Not only would the forcible territorial transfer be sanctioned, but it would also be happening with the approval of the United States, one of the norm’s historic champions.

The outcome of one war will not decide the norm’s fate, and a full revival of territorial conquest will not happen overnight. In other words, states are not likely to suddenly start making claims as bold as Russia’s in Ukraine. But as the international environment becomes more permissive of territorial claims, revisionist states may test boundaries with smaller-scale moves against weaker targets. Azerbaijan’s 2023 takeover of Nagorno-Karabakh, which elicited a minimal global response, is one recent example. Next, Sudan could seize the Amhara region of Ethiopia. China could adopt a more aggressive posture in the South China and East China Seas. Venezuela is already claiming large swaths of Guyana, and it could act more forcefully on those claims. The Palestinian territories, Taiwan, Western Sahara, and other polities that are not broadly recognized as sovereign states will be especially vulnerable. Even more worrying is the possibility of escalation in border conflicts among nuclear-armed states, such as China, India, and Pakistan.

As aggressors go unpunished, states may increasingly act on territorial claims.

Looking further ahead, if the norm against conquest continues to erode and countries no longer fear major reprisals for territorial aggression, threats that seem distant or far-fetched now could become real possibilities. Buffer states—those geographically located between rival countries—would be especially vulnerable to attack. Through the middle of the twentieth century, Poland was trampled and carved apart by wars between bigger powers. Today, other former Soviet satellite or socialist republics, stuck between NATO and an increasingly revanchist Russia, could face a fate similar to Ukraine’s. If Chinese-Russian relations turn sour, Mongolia, too, could be at risk, as neither of its more powerful neighbors will have any assurance that the other won’t act first to take over the state that separates them. Nepal and Bhutan, likewise, lie in precarious positions between China and India. Kuwait could once again be in danger, situated as it is between the regional rivals Iran and Saudi Arabia.

Related norms could also start to weaken. If territorial conquest is back on the table, states will be less likely to respect other elements of sovereignty, such as maritime rights. When small island states claim fishing and mining rights in exclusive economic zones, other countries in the region may simply ignore their claims. Might will disregard right. Violations of political sovereignty, from election meddling to regime change, may become not only more frequent but also more overt. Such breaches have always occurred, but norms have somewhat contained them and provided some recourse for weaker states. If the powerful no longer respect the rules, they undermine social restrictions on acts of violence against institutions, land, and people.

The erosion of the norm against territorial conquest could even precipitate a broader shift in an international system that is built on relations between sovereign states. Several challenges to sovereignty already loom, such as the threat posed by climate change to small island nations, or the way technology companies have assumed the communication, diplomatic, and military roles once reserved to governments. The return of territorial conquest would add to these pressures. If the survival of a state threatened by an aggressor is increasingly in doubt, that state’s ability to strike security and economic agreements will decline as well. And if state sovereignty becomes broadly precarious, it is not clear how the open markets that underpin the globalized order will operate. Conquest, furthermore, is fundamentally incompatible with democracy. Many tenets of the liberal international order cannot survive in the absence of the norm against territorial conquest. Perhaps that is the point.

PERMANENT DECLINE?

The norm against territorial conquest has undergirded U.S. power for the past eight decades, stabilizing the international system and enabling the United States to build a web of enduring alliances and to prosper from trade that is largely undisturbed by conflict. But it has not served all countries well. The norm itself rests on troubling foundations—its strongest proponents imposed rules on the rest of the world after centuries of colonialism in which they redrew borders at will, and in the decades since they have repeatedly flouted their own rules and violated the sovereignty of weaker states. Weaker countries also suffer most as a result of the perverse incentives the norm produces. Knowing that their borders are largely secure, avaricious leaders can divert resources to internal security and repression while they plunder state coffers, creating the conditions for instability, civil war, and state failure.

Yet the norm against territorial conquest has also held in check the cruelty that accompanies wars of annexation. As the political scientist Alexander Downes has shown, armies deployed to take territory often target civilians, too. The brutality of Russian forces in Ukraine and deportations carried out by Azerbaijani forces in Nagorno-Karabakh are only the most recent examples. Conquest may involve ethnic cleansing, as illustrated in the recent U.S. proposal, supported by Israel, to empty the Gaza Strip and move its population to nearby countries. At a basic level, conquest ignores the will of local populations; Western Guyanese do not wish to be part of Venezuela, just as Ukrainians do not want to join Russia.

Norms lose their potency when they do not keep powerful states from doing what they want.

The permanent decline of the norm—and the disorder that could follow its demise—is not a foregone conclusion. A more transactional understanding of territory, along the lines of Trump’s proposals for the United States to purchase Greenland, develop Gaza, and renegotiate rights to the Panama Canal, is unlikely to replace it. People’s attachment to their homelands and the pull of forces such as nationalism are too strong, and pursuing deals that ignore both could invite large-scale, violent pushback.

Even if the United States abdicates its traditional enforcement role, other key powers that benefit from the relative peace the norm enables could step in. China, for example, rose to power within the institutional architecture of the postwar international order and has always zealously guarded its own sovereignty. It is possible that China could take a page from U.S. history and chart a similar trajectory of territorial expansion followed by global leadership. Beijing might first take advantage of the norm’s relative weakness to satisfy its territorial ambitions by absorbing Taiwan and cementing its island and maritime claims in the South China and East China Seas. But afterward, it might seek to enforce some restrictions on conquest—still allowing limited interference in other countries, but threatening an economic or military response to those who engage in territorial aggression, especially in China’s own region, to prevent the kind of disorder that would undermine its economic and security interests. Such behavior would be hypocritical, but sovereignty norms have always been shot through with hypocrisy; witness the repeated foreign interventions by the United States, long these norms’ most important champion.

Still, any move toward a watered down or distorted version of the current norm against territorial conquest would lead to a rise in conflict over land. Since World War II, many countries have grown accustomed to and benefited greatly from the relative stability of the U.S.-led order and the respect for territorial sovereignty it enforces. It is difficult to pinpoint how far the system could unravel if current constraints on territorial conquest continue to erode. But weak and strong countries alike will surely miss the norm when it’s gone.