What the international community can do to support regime change in Libya.

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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