Kevin Jon Heller is Professor of International Law and Security at the University of Copenhagen and Professor of Law at the Australian National University.
Editor's note: This article is adapted from a paper presented at a workshop, "Human Rights Go to War," that was convened by DAWN and co-sponsored by the Schell Center for International Human Rights at Yale Law School.
Many international lawyers and human rights NGOs believe that, in certain circumstances, states have the right to engage in unilateral humanitarian intervention—using force on the territory of another state to prevent mass atrocity without authorization from the United Nations Security Council. That belief raises two important issues. The first is positivist: whether unilateral humanitarian intervention is permitted by international law. The second is normative: whether such intervention should even be permitted by international law.
I address both issues in a recent article in the European Journal of International Law. I will not reiterate the legal analysis here; suffice it to say that I think unilateral humanitarian intervention violates the prohibition of the use of force in Article 2, Section 4 of the U.N. Charter and amounts to the crime of aggression under Article 8 bis of the Rome Statute. The use of force claim, I think, is simply undeniable: Only two states have ever specifically endorsed the legality of unilateral humanitarian intervention—the United Kingdom and Denmark—while more than 140 states, representing almost the entirety of the global south, have specifically condemned it as unlawful. As for the aggression claim, I explain in my EJIL article why the drafting history of Article 8 bis makes clear that unilateral humanitarian intervention does not fall into the kind of legal "gray area" that would exclude it from the crime of aggression.
The legal issue, however, is distinct from the normative one. Even if unilateral humanitarian intervention is unlawful and criminal, it could still be a good idea for states to unilaterally use force to protect civilians. Conversely, even if unilateral humanitarian intervention is lawful, it could still be a bad idea for states to unilaterally use force to protect civilians. The normative question depends not on law but on how we answer two empirical questions. First, are states likely to unilaterally use force for genuinely humanitarian purposes? And second, are genuinely humanitarian unilateral interventions likely to effectively prevent mass atrocity?
My answer to both questions is the same: Definitely not.
We should avoid uncritically accepting a state's claim to be acting for humanitarian reasons. States that do not have to worry about legally justifying their uses of force—because their power effectively prevents them from being held accountable—are very likely to use civilian protection as a pretext for pursuing more base interests.
- Kevin Jon Heller
Does Genuine Unilateral Humanitarian Intervention Exist?
If history is any guide, states are extremely unlikely to engage in genuine unilateral humanitarian intervention. Very few of the past uses of force that scholars have cited in defense of such intervention were even primarily motivated by humanitarian concerns.
It is not easy, of course, to determine whether a state's motivation for engaging in a unilateral intervention. Three interpretive principles, however, seem particularly relevant to that inquiry. The first is that the starting point of the analysis must be how the state itself justified its intervention. It is more than a little hubristic to insist that a state's primary motivation for using force was humanitarian if that state did not even mention humanitarian concerns at the time. For example, although the American invasion of Grenada might have had positive humanitarian consequences, the United States not only declined to invoke a right of unilateral humanitarian intervention, it even specifically disclaimed it.
The second principle is the corollary of the first: We should also avoid putting too much emphasis on how a state formally justified a particular use of force. Given the overwhelming evidence that unilateral humanitarian intervention is unlawful, a state acting for genuinely humanitarian reasons has a strong incentive to invoke a more traditional legal rationale, such as self-defense.
The third principle follows from the first two: When assessing an intervening state's motives, we should avoid uncritically accepting a state's claim to be acting for humanitarian reasons. States that do not have to worry about legally justifying their uses of force—because their power effectively prevents them from being held accountable—are very likely to use civilian protection as a pretext for pursuing more base interests. The most notorious example is the U.S. invasion of Iraq in 2003, which was flagrantly illegal under international law but which the U.S. government cynically tried to sell to the public as a mission of hope for Iraqis suffering under Saddam Hussein's regime.
Whether a particular use of force qualifies as unilateral humanitarian intervention, in short, must be determined on a case-by-case basis, paying attention not only to the intervening state's public rationales—legal and otherwise—but also to the actual situation on the ground. Even so, it is still very difficult to find unilateral interventions that were motivated primarily by humanitarian concerns. Consider three early interventions that scholars often cite in defense of unilateral humanitarian intervention: in East Pakistan, Uganda and Cambodia.
To justify its intervention in what was then East Pakistan in 1971, India claimed in the U.N. Security Council that it had "absolutely nothing but the purest of motives and the purest of intentions: to rescue the people of East Bengal from what they are suffering." Scholars generally agree, however, that India's primary motivation was to protect itself against a massive influx of refugees and that India viewed the invasion as a way of expanding its influence in Southeast Asia.
Although Tanzania occasionally condemned Ugandan dictator Idi Amin's human rights abuses, it justified recovering its territory and then invading Uganda in 1978 as self-defense, not as a humanitarian mission. It is also clear that Tanzania invaded Uganda intending to overthrow Amin and install a more friendly government. Simon Chesterman has thus concluded that "humanitarian motives may have been operative but were far from paramount."
While there is little question that, on balance, Vietnam's destruction of the Khmer Rouge regime had positive humanitarian effects, its 1978 invasion of Cambodia—then known as Democratic Kampuchea under the Khmer Rouge—was not primarily humanitarian. On the contrary, Vietnam was acting on imperial ambitions in the area and—as it publicly claimed—the need to defend itself against repeated Cambodian cross-border attacks.
Scholars have highlighted a number of more recent interventions as motivated, at least in part, by humanitarian concerns: Northern Iraq in 1991, Somalia in 1992, Haiti in 1994, Rwanda in 1994, Bosnia in 1995, Kosovo in 1999, East Timor in 1999, Afghanistan in 2001, Iraq in 2003, Libya in 2011, and Syria in 2018. Andreas Krieg concluded in a recent study, however, that only three of the first nine (his study did not include Libya or Syria) were primarily humanitarian: northern Iraq, Somalia and East Timor. Moreover, his study provides little evidence that states are willing to intervene unilaterally to protect civilians from harm, because the interventions in Somalia and East Timor were authorized by the Security Council. (Even in the case of Somalia it's close, as Krieg notes that President George H.W. Bush had a very strong political interest in U.S. intervention, given the upcoming presidential elections in 1992 and Democratic rival Bill Clinton's constant criticism of Bush for neglecting foreign policy.)
That leaves only one intervention, northern Iraq, as a "true" unilateral humanitarian intervention—and even that is questionable, because it can also be argued that the international coalition was primarily motivated to intervene in Iraq in 1991 by the need to prevent Turkey from being destabilized by a massive influx of Kurdish refugees and to limit Iran's influence in the region. (In a rare show of transparency, the U.S. also openly admitted that it hoped the no-fly zones would help undermine Saddam Hussein's government.)
Krieg's conclusion that all the other interventions were driven primarily by non- humanitarian concerns is consistent with the available evidence. Despite comments by various states about the humanitarian crisis in Haiti, the Security Council-authorized intervention in 1994 was primarily motivated by two American desires: to minimize the economic problems created by an influx of Haitian refugees and, later, to restore democracy to a state within the U.S. sphere of influence.
Although France repeatedly insisted it intervened in Rwanda in 1994 solely for humanitarian reasons, scholars generally agree that national self-interest predominated, particularly the desire to prevent Rwanda from moving into the Anglo-American sphere of influence. Indeed, the lack of France's genuinely humanitarian concern is foregrounded by the fact that it not only supported the Hutu government even when it was threatened by the Rwandan Patriotic Front, but also chose not to intervene in Rwanda until the worst of the genocide was over.
Although the NATO intervention in Bosnia in 1995 might have had humanitarian effects, NATO stood on the sidelines for nearly three years while Serbs engaged in atrocities, which culminated in the massacre of some 8,000 civilians in Srebrenica. When NATO did finally intervene, it did so primarily to restore its battered credibility, to prevent a wider conflict in the Balkans, and to staunch the flow of refugees into NATO states such as Germany.
In 1999 in Kosovo, often held up as the "model" of unilateral humanitarian intervention, there is no question that humanitarian concerns played a significant role in NATO's decision to intervene. It is unlikely, however, that such concerns were NATO's primary motivation. On the contrary, scholars believe that NATO intervened unilaterally in Kosovo for substantially the same reasons it had intervened four years earlier, with the Security Council's blessing, in Bosnia: credibility, conflict containment and refugees. Their skepticism seems warranted, especially as NATO limited its "humanitarian intervention" to high-altitude aerial bombing, despite having been warned that doing so was more likely to worsen the situation in Kosovo than to improve it.
The intervention in Afghanistan in 2001 was not primarily motivated by humanitarian concerns, despite occasional U.S. suggestions to the contrary. Not only did the U.S. formally claim that it was acting in self-defense after 9/11, it also constantly emphasized that the goal of Operation Enduring Freedom was to destroy al-Qaida's ability to launch terrorist attacks against the U.S. and its allies.
The predominance of non-humanitarian motives for the subsequent U.S. invasion of Iraq in 2003 needs little comment. As Krieg says, the invasion "lack[ed] any altruistic component" whatsoever. Instead, the U.S. was overwhelmingly motivated by the desire to remove Saddam Hussein from power and to protect American economic interests in the region.
States almost never intervene in atrocity situations primarily for humanitarian reasons—not even when they have the blessing of the U.N. Security Council. And when states do intervene, for humanitarian reasons or otherwise, they almost always make the situation on the ground worse.
- Kevin Jon Heller
NATO's intervention in Libya in 2011, which Krieg does not discuss, presents a closer case. Security Council Resolution 1973, which formed the legal basis for the Libyan military intervention, itself clearly had a humanitarian purpose, given that it authorized member states "to take all necessary measures… to protect civilians and civilian populated areas under threat of attack." There is considerable evidence, however, that the states that led NATO's intervention —the U.S., the U.K. and France—were primarily motivated by the desire to remove Muammar Gaddafi from power. As a number of scholars have noted, many of NATO's actions, particularly its refusal to heed the Libyan government's almost immediate entreaties to negotiate a cease-fire following the Security Council's authorization of a no-fly zone under Resolution 1973, are difficult to explain on humanitarian grounds.
The other intervention Krieg does not discuss—the military strikes in Syria in 2018 by the U.S., the U.K. and France, following a suspected chemical attack by the Syrian government on civilians near Damascus—is even more difficult to classify as primarily humanitarian. The U.K. was the only intervening state that exclusively cited the need to protect civilians. France mentioned humanitarian concerns but emphasized the need to enforce international prohibitions on the use and proliferation of chemical weapons. And the U.S., though also mentioning the ongoing humanitarian catastrophe in Syria, made very clear that its primary motivation was preventing the use of chemical weapons against Americans, not against Syrians. As then-President Donald Trump said immediately after the attacks, "[t]he purpose of our actions tonight is to establish a strong deterrent against the production, spread and use of chemical weapons. Establishing this deterrent is a vital national security interest of the United States."
It is also important not to take the U.K.'s ritualistic invocation of unilateral humanitarian intervention in Syria at face value. As Marko Milanovic has noted, had the U.K. truly been motivated primarily by humanitarian concerns, it would have supported a far greater intervention. Instead, like the U.S., it chose to support a limited military response that stood no chance of significantly improving the humanitarian situation on the ground.
Does Genuine Unilateral Humanitarian Intervention Work?
The extreme rarity of unilateral humanitarian intervention is enough to question its desirability. The normative case for unilateral humanitarian intervention also assumes, however, that such intervention is likely to be effective. If unilateral humanitarian intervention exists but almost always makes the humanitarian situation in the territorial state worse, it is difficult to see why it would be problematic to prohibit or even criminalize it.
Yet that is precisely what the historical record indicates. It is difficult enough to find even one example of successful non-unilateral humanitarian intervention. The only credible exception is East Timor, where the intervention helped bring stability to the island and made possible Timorese independence from Indonesia. Even there, though, there is reason to temper praise for the intervention. Australia helped create the humanitarian problem in the first place, because, as Nicholas J. Wheeler has written, it "knew Indonesia was preparing to conquer East Timor in 1975, may have provided tacit approval, and were willing to arm Suharto's regime in the years preceding the conquest."
By contrast, it is easy to identify unsuccessful Security Council-authorized humanitarian interventions. Somalia and Libya are indicative examples. With regard to the former, although some scholars believe U.S. intervention initially saved some Somalis from starvation—still a controversial claim—"[w]hat is not disputed is that the mission ended in disaster," as Wheeler and Alex Belamy note. Despite the intervention leading to the U.N.'s most significant state-building operation to date, Somalis have rarely had a functioning central government since then, have experienced almost endless violence and conflict, and have routinely suffered from mass starvation.
If anything, the consequences of NATO's "humanitarian" intervention in Libya have been even worse. Not only has the lack of a functioning state "been filled by militias that defy the central government and by armed Islamist groups that pursue a millenarian agenda," as Rajan Menon writes, the entire region is now "more hospitable to groups trafficking in religious extremism and violence than it had been while Gaddafi was in power.
There is little reason to believe that genuinely humanitarian unilateral intervention is any more effective at ending mass atrocity. The three most successful interventions—East Pakistan in 1971, Uganda in 1978 and Cambodia in 1978—took place more than four decades ago, and none of the intervening states were primarily motivated by humanitarian concerns. By contrast, the U.S., the U.K. and France's collective intervention in northern Iraq in 1991 might have had a genuinely humanitarian purpose, but it did not solve the Kurdish problem, as the subsequent decades have made clear. Moreover, Operation Provide Comfort convinced the U.S. and the U.N. that successful humanitarian intervention could be accomplished with relative ease using primarily air power and/or lightly armed peacekeepers. That "creeping unilateralism" later proved disastrous in Somalia, Srebrenica and Kosovo.
Indeed, it is difficult to overstate the failure of NATOs intervention in Kosovo, which was deliberately limited to high-altitude bombing to protect NATO soldiers. To begin with, it was precisely the prospect of "humanitarian" intervention that led to serious and likely avoidable violence by both the Kosovo Liberation Army and the Serbs. As Alan J. Kuperman observed:
The rebels expected to benefit from humanitarian intervention if they provoked the violence because of precedents and signals from the international community… Because the KLA strategy was based on attracting humanitarian intervention, but the rebels harbored no hope of prevailing themselves, violence might well have been averted if not for the moral hazard of humanitarian intervention.
As predicted by many, including the presidents of Slovenia and Macedonia, NATO's bombing campaign—what Edward Luttwak called the first "post-heroic" war—not only failed to improve the humanitarian situation on the ground, it also made it vastly worse. In the three months after the first bombs began to fall, Serbs killed nearly 10,000 Kosovar civilians—five times the number killed before the campaign began. The bombing also displaced another 1.4 million, almost 90 percent of Kosovo's population, many of whom fled to neighboring states, creating a massive refugee crisis.
The U.K., the U.S. and France's limited intervention in Syria in 2018 also failed to create positive humanitarian effects. At least 12,000 civilians have been killed since their April 2018 airstrikes. That number is not surprising, given that the intervention was primarily motivated by the desire to limit the proliferation of chemical weapons, not to protect Syrian civilians from harm. And even that purpose has been at best a qualified success. The Syrian government has continued to use chemical weapons against civilians despite the airstrikes.
Uncomfortable Truths
There is no denying that unilateral humanitarian intervention is a seductive concept. What decent human being wouldn't support such intervention, despite its illegality under international law, if it could save the lives of thousands of innocent civilians? Indeed, if the possibility of genuine and effective unilateral humanitarian intervention is real, shouldn't we want it to be lawful and not simply—to quote the famous statement by the Independent International Commission for Kosovo—"illegal but legitimate"?
It is precisely the hope for a better world, and a better international law, that leads so many international lawyers and human rights NGOs to cling tenaciously to the possibility of unilateral humanitarian intervention. Unfortunately, it is not apology to respond to the utopia of unilateral humanitarian intervention by pointing out that the normative case for such intervention is based on two ideas that are each profoundly flawed. States almost never intervene in atrocity situations primarily for humanitarian reasons—not even when they have the blessing of the U.N. Security Council. And when states do intervene, for humanitarian reasons or otherwise, they almost always make the situation on the ground worse.
Neither of those uncomfortable truths should surprise is. You don't have to be an arch-realist to question how often states will be willing to spend significant blood and treasure to protect another state's civilians. The name might be sterile, but the reality is anything but: Unilateral humanitarian intervention involves one state invading another and then using enough violence against the invaded state's armed forces to stop them from committing atrocities. And you don't have to be a pacifist to question whether mass violence is an effective method for stopping mass violence. Violence is violence, no matter what its motivation.
