Read more of Slate’s coverage of the Libyan protests.

During an otherwise bizarre, incoherent speech on Tuesday, Libyan leader Muammar Qaddafi clarified one thing: He is ready and willing to slaughter his own people if his survival requires it.

In confirming what many had already suspected, Libya has moved from one stage of conflict to another. The more appropriate model here is not Egypt or Tunisia but rather Bosnia, Kosovo, or Iraq after the first Gulf War—civil conflicts in which leaders perpetrated premeditated, mass killing of noncombatants.

Only a few days after pro-democracy protests first broke out, the death toll has risen as high as 1,000, according to some estimates. It is likely to get worse, threatening a repeat of Syrian President Hafez Assad’s destruction of Hama in 1982, which claimed at least 10,000 lives. To prevent a similar outcome, the international community—specifically the United States, the United Nations, and NATO—must intervene.

The international response to the Libyan crisis has so far been lacking in both vision and resolve. Initial reactions, with their by now tiresome phrasing—”expressing grave concern” and “urging restraint”—suggested a limited vocabulary that was not commensurate with the gravity of the crimes being committed. Washington has threatened to consider “all appropriate action,” but Western officials have been slow to specify what that might be. In its place is a general sense that the United States and its allies have limited leverage.

We are, however, well beyond leverage. Qaddafi and his family do not seem in the mood for negotiation or compromise. Their promise to fight to the “last drop of blood” has said as much. The objective, then, is not to pressure Qaddafi and his sons but to support pro-democracy forces and encourage regime defections to the opposition. The goal is no longer change but regime change.

Regime defections will mount if the momentum continues to shift. Already, the government is losing control over its territory, with Benghazi, the country’s second-largest city, falling to anti-Qaddafi forces. That momentum will build if Libyans see that the international community is not only watching but acting.

What can be done? This is a time for bold, creative policy-making. For starters, NATO should quickly move to enforce a no-fly zone over Libya, both to send a strong message to the regime and to prevent the use of helicopters and planes to bomb and strafe civilians. The United States and European allies should freeze the assets of senior Libyan officials and consider other targeted sanctions. Meanwhile, the international community should also let it be known that any individuals involved in perpetrating atrocities will be prosecuted before the International Criminal Court, while regime figures who defect to the opposition will be granted amnesty.

If the conflict threatens to spill over into outright civil war, and the death toll reaches into the tens of thousands, the United Nations will need to consider more advanced measures, including authorizing the deployment of peacekeeping troops to protect civilian populations in the eastern part of the country.

At such a critical moment, it is unfortunate that the Bush administration’s destructive adventurism in Iraq tainted the notion of humanitarian intervention. Understandably, the world is wary of aggressive Western interference in the affairs of other states. Libya, in this respect, provides a critical test for the effectiveness of the United Nations, norms of humanitarian protection, and international law more generally.

Under Chapter VII of the U.N. charter, the organization has a mandate to intervene, as appropriate, to respond to “any threat of the peace, breach of the peace, or act of aggression.” Invoking Chapter VII would be a good first step to advance the debate about appropriate policy tools and to internationalize the mode of response, in accordance with international legal conventions.

The “responsibility to protect” provides further grounds for action. During the 2005 U.N. World Summit, member states unanimously affirmed that “each individual State has the responsibility to protect its populations from genocide, war crimes, ethnic cleansing, and crimes against humanity.” In Paragraph 139 of the summit outcome document, states affirmed their readiness to take collective action “in a timely and decisive manner” if nations “manifestly fail” to protect their populations from crimes against humanity.

In not only failing to protect its population but in taking active, public steps to wage war against its own people, Libya has forfeited its claims to sovereignty. There will be traditional realists who tell us that this is not our battle to fight, and leftists who cannot move beyond their suspicion of America’s imperialist designs. Unfortunately, though, there is no one else with the ability to stop mass killing. And that must be the top priority.

This is not just about Libya. The broader region is both coming alive and coming apart. Across the Arab world, governments are using disturbing levels of violence against peaceful protesters, and as long as their survival is at stake, they will continue to do so. Before the region descends into protracted civil conflict or worse, the international community has the opportunity, in Libya, to set an important precedent and save thousands of lives in the process.

Aggressive international action is risky. But taking comfort in toothless denunciations of Qaddafi is riskier still. It is also a recipe for prolonged conflict. In the absence of alternatives, a responsibility to protect sometimes necessitates a responsibility to intervene. And, with the Libyan regime declaring, with unmistakable clarity, its intent to kill, the time for intervention is now.

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