When should states intervene militarily to stop atrocities in other countries? The question is an old and well-traveled one. Indeed, it is now visiting Syria.
In 1904, U.S. President Theodore Roosevelt, referring to Cuba, argued that the United States should intervene by force of arms when "there are occasional crimes committed on so vast a scale and of such peculiar horror." A century earlier, in 1821, as Europeans and Americans debated whether to intervene in Greece's struggle for independence, U.S. President John Quincy Adams warned his fellow Americans about "going abroad in search of monsters to destroy."
More recently, after a genocide that cost nearly 800,000 lives in Rwanda in 1994 and the slaughter of Bosnian men and boys at Srebrenica in 1995, many people vowed that such atrocities should never again be allowed to occur. When Serbian leader Slobodan Milosevic engaged in large-scale ethnic cleansing in Kosovo in 1999, the United Nations Security Council adopted a resolution recognizing the humanitarian catastrophe but could not agree on a second resolution to intervene, given the threat of a Russian veto. Instead, NATO countries bombed Serbia in an effort that many observers regarded as legitimate but not legal.
In the aftermath, then-UN Secretary-General Kofi Annan created an international commission to recommend ways that humanitarian intervention could be reconciled with Article 2.7 of the UN Charter, which upholds member states' domestic jurisdiction. The commission concluded that states have a responsibility to protect their citizens. If a nation disregards that responsibility by attacking its own citizens, the international community can consider armed intervention.
The Responsibility to Protect principle was adopted unanimously at the UN's World Summit in 2005, but subsequent events showed that not all member states interpreted the resolution the same way. Russia has consistently argued that only Security Council resolutions, not General Assembly resolutions, are binding international law. Meanwhile, Russia has vetoed a Security Council resolution on Syria. Somewhat ironically, Annan has been called back and enlisted in a so-far futile effort to stop the carnage there.
Until last year, many observers regarded the Responsibility to Protect principle as, at best, a pious hope or a noble failure. But in 2011, as Libyan leader Moammar Gadhafi prepared to exterminate his opponents in Benghazi, the Security Council invoked the Responsibility to Protect principle as the basis for a resolution authorizing NATO to use armed force in Libya. U.S. President Barack Obama was careful to wait for resolutions by the Arab League and the Security Council, thereby avoiding the costs to U.S. soft power that former U.S. President George W. Bush suffered when the country intervened in Iraq in 2003. But Russia, China and other countries felt that NATO exploited the resolution to engineer regime change rather than merely protecting citizens in Libya, as the resolution wording stipulated.
In fact, the Responsibility to Protect is more about struggles over political legitimacy and soft power than it is about hard international law. Some Western lawyers argue that it entails the responsibility to combat genocide, crimes against humanity and war crimes under various conventions of international humanitarian law. But Russia, China and others have become reluctant to provide a legal or political basis for actions such as what occurred in Libya.
There are other reasons why Responsibility to Protect has not been a success in the Syrian case. Drawn from traditional "just war" theory, Responsibility to Protect rests not only on right intentions, but also on the existence of a reasonable prospect of success. Many observers highlight the important physical and military differences between Libya and Syria that would make Syrian no-fly zones or no-drive zones problematic. Some Syrians who oppose President Bashar Assad's regime, pointing to Baghdad in 2005, argue that the one thing worse than a cruel dictator is a sectarian civil war.
Such factors are symptomatic of larger problems with humanitarian interventions. For starters, motives are often mixed. Moreover, we live in a world of diverse cultures, and we know very little about social engineering and how to build nations. When we cannot be sure how to improve the world, prudence becomes an important virtue, and hubristic visions can pose a grave danger. Foreign policy, like medicine, must be guided by the basic principle "Do no harm."
Prudence does not necessarily mean that nothing can be done in Syria. Other governments can continue to try to convince Russia that its interests are better served by getting rid of the current regime than by permitting the continued radicalization of his opponents. Tougher sanctions can continue to delegitimize the regime, and Turkey might be persuaded to take stronger steps against its neighbor.
Moreover, prudence does not mean that humanitarian interventions will always fail. In some cases, even if motives are mixed, the prospects of success are reasonable, and the misery of a population can be relieved at modest expense. For example, military interventions in Sierra Leone, Liberia, East Timor and Bosnia did not solve all problems, but they did improve the lives of the people there. Other interventions — for example, in Somalia — did not.
Recent large-scale interventions in Iraq and Afghanistan, though not primarily humanitarian, have eroded public support for military action. But we should recall U.S. writer Mark Twain's story about his cat. After sitting on a hot stove, it would never sit on a hot stove again, but neither would it sit on a cold one.
Although interventions will continue to occur, they are now more likely to be shorter, involve smaller-scale forces and rely on technologies that permit action at a greater distance. In an age of cyber warfare and drones, the end of Responsibility to Protect or humanitarian intervention is hardly foretold.
Joseph Nye is a professor at Harvard University and author of "The Future of Power." © Project Syndicate