The Prohibition of Annexations and the World on the Brink

The International Court of Justice (ICJ) decided last week that Israel has acted to unlawfully annex Palestinian territory. The opinion is a clear rebuke to Israel and may affect the course of future relations with Israel and Palestine. As important as that is, the opinion should also be seen in a broader social and political context. The court has sent the world a clear message: Annexations of territory are not, in any form, permissible and must not be tolerated. That message comes at a time when, as we explain in a forthcoming article, the norm prohibiting annexations is at serious risk of erosion, with potentially devastating consequences for the world.

The ICJ Opinion

In its advisory opinion in Legal Consequences Arising from the Policies and Practices of Israel in the Occupied Palestinian Territory, Including East Jerusalem on July 19, which focused primarily on Israel’s conduct prior to Hamas’s Oct. 7, 2023, attack, the ICJ restates long-standing international legal rules governing occupations: Occupying powers have “a duty to administer the territory for the benefit of the local population” (para. 105). Moreover, “occupation is a temporary situation to respond to military necessity, and it cannot transfer title of sovereignty to the occupying Power.” The court broke new ground in finding that Israel is an occupying power not only in the West Bank and East Jerusalem but also in the Gaza Strip, notwithstanding Israel’s 2005 withdrawal from Gaza. The court went on to decide that Israel’s occupation has violated a host of international legal norms, including the Palestinians’ right to self-determination and the norm that prohibits forcible annexations of foreign territory. The court thus decided that the occupation had become unlawful.

According to the ICJ, Israel’s violations generate obligations for a host of global actors, reflecting the serious nature of the harms involved. Some of these obligations, of course, fall on Israel. The court decided that Israel is obligated to bring an end to the unlawful occupation as rapidly as possible, including through a cessation of all settlement activity and the repeal of all measures that create or maintain the occupation or that work to discriminate against Palestinians in the Occupied Palestinian Territory. In addition, the court determined that Israel must “provide full reparation for the damage caused by its internationally wrongful acts to all natural or legal persons concerned,” a potentially monumental burden (para. 269).

The ICJ also imposed significant obligations on other states. It noted that Israel’s conduct violated what are known as erga omnes obligations—obligations that “are by their very nature ‘the concern of all States’” the protection of which “‘all States can be held to have a legal interest’” (para. 274). The court then determined that, “in view of the character and importance of the rights and obligations involved,” every state has an obligation (paras. 278, 279)

not to recognize any changes in the physical character or demographic composition, institutional structure or status of the territory occupied by Israel on 5 June 1967, including East Jerusalem, except as agreed by the parties through negotiations and to distinguish in their dealings with Israel between the territory of the State of Israel and the Palestinian territory occupied since 1967.

The opinion is absolutely clear that “[i]t is for all States,” not only for Israel, “to ensure that any impediment resulting from the illegal presence of Israel in the Occupied Palestinian Territory to the exercise of the Palestinian people of its right to self-determination is brought to an end” (para. 279). States must thus “abstain from entering into economic or trade dealings with Israel concerning the Occupied Palestinian Territory or parts thereof which may entrench its unlawful presence in the territory” and “from any recognition of its illegal presence in the Occupied Palestinian Territory” (para. 278).

The ICJ likewise imposed on international organizations, including the United Nations, a duty of non-recognition of the illegal situation in the Occupied Palestinian Territory. The court specifically called on the UN General Assembly and the UN Security Council to determine the “precise modalities” that should be taken “to bring to an end Israel’s unlawful presence in the Occupied Palestinian Territory” (para. 281). Here, the court repeated a warning from its 2004 advisory opinion on the Legal Consequences of the Construction of a Wall in the Occupied Palestinian Territory, about the “‘urgent necessity for the United Nations as a whole to redouble its efforts to bring the Israeli-Palestinian conflict ... to a speedy conclusion’” (para. 282).

The ICJ ended with a strong statement of the policy rationale for imposing such an extensive set of obligations not only on Israel but also on the rest of the world (para. 283):

the realization of the right of the Palestinian people to self-determination, including its right to an independent and sovereign State, living side by side in peace with the State of Israel within secure and recognized borders for both States, as envisaged in resolutions of the Security Council and General Assembly, would contribute to regional stability and the security of all States in the Middle East.

The court’s broader message emerges forcefully from the opinion. Annexations of territory, evinced by the intent to acquire foreign territory through the assertion of physical control, are absolutely prohibited. Even creeping annexations, of the sort that Israel has conducted, are unlawful. One need not look for a single massive event, like Russia’s 2022 invasion of Ukraine, to “see” an annexation in effect. Annexations in general are among the most serious of international legal violations not because they involve a visible and dramatic use of force but because they involve a state’s unlawful entrenchment of its own authority in territory that does not belong to it, infringe on the right to self-determination of the people who live there, and in light of their history—which instigated both world wars and the horrific acts of European colonialism—pose serious threats to national and human security.

Territorial Conflicts

Although we disagree with some of the ICJ’s logic, its basic message supports our argument that the prohibition of annexations is foundational to modern international law. As the court’s opinion makes clear, this is a path down which the world should not go. What follows is almost certainly large-scale human suffering. Yet three trends suggest that this is where the world is increasingly headed.

First, since Russia’s 2022 attack on Ukraine, we have witnessed the rapid expansion and consolidation of competing security alliances. NATO is (for now) as strong as ever, with Finland and Sweden having joined recently and more of its members ramping up their support. In addition, the United States has fortified its security alliances in the Indo-Pacific, with Japan, South Korea, Australia, New Zealand, the Philippines, Taiwan, India, and Vietnam, and in the Middle East, with Israel and a number of Sunni Arab states. Meanwhile, the United States’s staunchest adversaries—Russia, Iran, North Korea, and China—have been building and strengthening their own alliance, while each of these states flexes its nuclear capabilities. The trend to solidify antagonistic security alliances would by itself be troubling because, as Paul Poast has recently explained (citing the work of William Langer), “rapid movements toward alliance formation and consolidation often precede the outbreak of major wars,” including World Wars I and II. Once such alliances are fortified, even local or regional conflicts, such as the ones in Ukraine and between Israel and Palestine, can more easily be internationalized—as has happened in both of these conflicts.

Second, even aside from outright annexations, territorial conflicts around the world have escalated recently. The Ukraine and Israel-Palestine conflicts are both long-standing and profoundly destabilizing conflicts about who will have sovereign title to territory. But these are just two of many active or bubbling territorial conflicts around the world. Current conflicts on the border of China and India, between Ethiopia and Sudan, over Taiwan, and in Guyana, Nagorno-Karabakh, Western Sahara, the South China Sea, and beyond are also about assigning title to territory and, by extension, the maritime zones that accompany it.

Extensive research in history and political science shows that disputes over territory are more dangerous than other kinds of interstate disputes and that those involving claims of historic ownership are the most difficult to resolve. The prohibition of annexations is critical to preventing such conflicts, because this prohibition in effect locks territorial allocations in place, making them harder to change. Conversely, an erosion of this prohibition increases the prospects for acquiring territory by force and thus the incentives to renew old grievances over historic claims.

This second trend—the increase in territorial conflicts around the world—is especially dangerous in light of the first (the rise in antagonistic security alliances). All four states in alliance against the United States are now flexing their muscles to control territories that the United States is committed to protecting. As is now well known, Russia first acted to annex the Crimea region of Ukraine in 2014. At the time, Russia claimed that it intervened in Crimea at the invitation of local officials and to further the self-determination of the Crimeans, as expressed in a highly disputed referendum that was modeled expressly after Kosovo’s 2008 declaration of independence. Most states rejected Russia’s claim in a UN General Assembly resolution, but Russia maintained control of Crimea and used it as the base to wage a broader conflict in Ukraine. In 2022, it finally acted to annex all of the territory of Ukraine, in what has been a brutal conflict. Although the United States and its security allies have tried to isolate Russia for the attack on Ukraine, the other states in Russia’s alliance—Iran, North Korea, and China—have all actively or passively supported it. There is also evidence that Ukraine is just one of the neighboring states over which Russia seeks to exert more control.

The situation in Israel and Palestine is further evidence of the intersection of the above two trends. Although Israel has long occupied the territories that it seized in the 1967 war, it increasingly has also advanced claims to sovereign title over these territories. For example, in April 2016, Israeli Prime Minister Benjamin Netanyahu for the first time held a cabinet meeting in the Golan Heights, a small strip of land over which Syria has title, “to send a clear message: The Golan will always remain in Israel’s hands. ... [T]he Golan is an integral part of the State of Israel.” In 2019, the United States recognized Israel’s sovereignty in the Golan, in violation of the duty not to recognize territories that are forcibly annexed.

Apart from the Golan, Israeli officials have also increasingly claimed sovereignty in the West Bank and East Jerusalem. A UN commission concluded in September 2022 that Israel has, “to all intents and purposes, ‘annexed’ wholly or partly the Occupied Palestinian territory,” not only Golan. The recent advisory opinion clarifies that Israel is acting unlawfully to annex this territory. At the same time, Iran is acting through Hamas, Hezbollah, and other armed groups not only to make good on its vows to “eradicate” Israel but also to exert control in other territories in the region—most obviously in Yemen, Iraq, and Lebanon. These efforts at territorial aggrandizement are the backdrop against which the horrific conflict in Gaza is now being waged.

For years, China has also been militarizing its long-standing territorial disputes with its neighbors—around the South and East China Seas and in the Himalayan region—as well as with Taiwan. At least some of this conduct is reminiscent of the “creeping” style of annexation that Israel has used, slowly asserting physical control over territories that are not assigned to it. China’s apparent effort to annex foreign territory also butts up against an alliance that is being actively fortified against it. The United States is positioning itself against China through its hardening alliances with Japan, the Philippines, Australia, New Zealand, India, and, of course, Taiwan. Moreover, late last year, North Korea signaled a shift in its policy toward the South, another U.S. security ally, away from reconciliation and toward confrontation. It opened the possibility of, in North Korea’s words, “completely occupying, subjugating and reclaiming the [Republic of Korea] and annex[ing] it as part of the [North Korean] territory.”

And although the trend in territorial conflicts is especially dangerous in the context of competing great-power alliances, it is not limited to that context. Other states are also acting, with coercion, on their long-standing territorial claims—further eroding the prohibition of annexations. For example, Morocco has been moving closer to finalizing its annexation of Western Sahara, a non-self-governing territory in North Africa. Morocco occupies and claims the title based on historic ties, despite a 1975 advisory opinion by the ICJ that reasoned to the contrary and called for “the free and genuine expression of the will of the peoples of the Territory,” consistent with their right to self-determination. Since 2019, dozens of Arab and African states have broken with the practice of refusing to recognize Morocco’s sovereignty in Western Sahara by opening regional consulates to Morocco. In December 2020, the United States formally recognized Morocco’s sovereignty over Western Sahara, again violating the duty of non-recognition, as part of a deal to normalize relations between Morocco and Israel. Since then, Algeria, which has long backed the independence movement in Western Sahara, cut off diplomatic ties with and took other unfriendly measures against Morocco, raising concerns about the escalation of that territorial conflict.

In 2020, the conflict between Azerbaijan and Armenia over the Nagorno-Karabakh region—part of the Caucasus that lies at the outer edges of what were the Russian, Persian, and Ottoman empires—also flared up. Armed conflict over the region broke out in the late 1980s, and a 1994 ceasefire left Armenia in control of a portion of Azerbaijan that included Nagorno-Karabakh and surrounding territories. In early 2020, Azerbaijani forces, with strong support from Turkey, acted to recapture this territory, culminating in a November 2020 ceasefire with Azerbaijan back in control of some of it. The ceasefire did not hold. Last fall, Azerbaijan again launched a military operation to reclaim the remaining lost territory, with harsh consequences—what some have labeled an ethnic cleansing—for the people involved.

A number of other territorial conflicts have also been picking up steam. In December 2023, Venezuela moved to realize its claims to an oil-rich region that Guyana also claims and has long administered; Guyana has since accused Venezuela of increasing its military presence near the border, creating a tenuous security situation in the region. Also this year, Ethiopia entered into a land deal with Somaliland, a breakaway region in Somalia, to gain access to the Red Sea in a move that Somalia has pledged to fight. These disputes all highlight the ongoing salience of territory as a driver for military conflict. Each suggests that efforts at territorial aggrandizement are on the rise as states jockey for position in an era of changing global power dynamics.

The third trend, which reinforces the other two, is what appears to be an exhaustion of U.S. power. A decline in the ability or willingness of the United States to exercise the global power that it historically has displayed creates a vacuum that others inevitably try to fill, peacefully or not. Today, that vacuum is being filled by states that want to take territories that do not presently belong to them. Even if the United States had the political will to stand by all of its security commitments—which it might or might not have—it would not be able to do what is necessary to secure all of its security allies and partners at the same time, in the face of what are evidently growing threats against them. More of these allies and partners are likely to face coercive attacks on their territories, overt or indirect.

The Prohibition of Annexations

As we explain in our article, the prohibition of annexations is foundational to modern international law because it ties together what have been three central projects in the discipline for well over a century. One relates to the entrenchment of state authority in defined territorial borders; a second, to the use of force across such borders; and a third, to the right to self-determination of the people within such borders. Violating the prohibition of annexations threatens all three of these projects simultaneously, because the norm is integral to and helps to sustain each of them. If forcible annexations of territory become more common, the authority of states in their designated territorial units will become more susceptible to disruption by external forces.

The norm has always come with trade-offs. For example, the way that international law has allocated territory—and, with it, state authority—has contributed to the arbitrary separation of peoples and ecosystems; may make internal or cross-border ethnic conflict more likely; has provided the grounds for shielding from redress human rights abuses within particular states; has limited the migration of those fleeing war, poverty, and environmental devastation; has allowed for shirking on measures to protect the environment and to provide other global public goods; and has systematically and at a very large scale helped to reproduce past injustices to entire populations. In other words, the world order that the prohibition supports is deeply flawed.

But the world currently lacks any plausible alternatives that might replace territorially defined states as the main units for political organization in the world. The erosion of the prohibition of annexations—and, with it, the broader set of norms that protect states’ territorial borders from forcible change—threatens to have negative and long-lasting consequences. As the world is increasingly caught up in a contest about the future order, a critical question is whether new social and political forces can emerge to produce a better world order, without first taking us through another period in which territory is again up for grabs. If not, the horrors we have witnessed in Ukraine and the Occupied Palestinian Territory will likely repeat themselves in many other parts of the globe.

Conclusion

Thus, with the July advisory opinion, the ICJ has put the world on notice. Solving the Israel-Palestine situation is necessary not just to stop the suffering there but also to forestall other human suffering. The world needs, as the court says, to ensure the “right of the Palestinian people to self-determination, including its right to an independent and sovereign State, living side by side in peace with the State of Israel within secure and recognized borders for both States.” It must neither allow Israel to annex Palestinian territory nor allow Israel to be annexed by the increasingly militant forces that seek to completely eliminate it.

The failure to meet this challenge is often taken to be a purely geopolitical problem. But it is also a significant legal problem. Putting it in legal context ties it together with the importance of denying Russia a territorial victory in Ukraine and the need to maintain the territorial integrity of, and self-determination of the people in, the Western Sahara, along with measures to forestall other potential or attempted annexations, such as in the South China Sea. States should take the ICJ’s warning seriously and as an opportunity to find a positive path forward. However else they might jockey for power in the future world order, they should do whatever is necessary to reinforce the prohibition of annexations in all the settings in which it is now at risk.