When President Obama accepted his Nobel Peace Prize early this morning (U.S. time) in Oslo, Norway, he did so with the recognition of the irony in receiving the prize as the leader of a nation engaged in two wars at present, and most of his speech was, in fact, a discourse on war--when it is just, its price, and how it can be avoided.

Central to Obama's vision of war is the notion of international peacekeeping efforts--groups of nations joined together to both prevent conflict and engage in it when it's justified--such as it was, according to Obama's own examples, in the First Gulf War and U.S. and international efforts in the Balkans and Somalia in the 1990s.

Obama took the stage today with 7,000 more NATO troops committed to the war in Afghanistan, pledged as part of NATO's extended commitment based on the principle that an act of war on one of its nations--aka 9/11--is an act of war on all. That's 3,000 troops shy of what Gen. Stanley McChrystal and NATO Secretary-General Anders Fogh Rasmussen would prefer.

So, in the midst of this vision of war, and the philosophical arguments for international peacekeeping, President Obama laid out a case for international involvement in Afghanistan--and more of a shared commitment in international peacekeeping efforts, in general, his implication being that the U.S., as the world's lone military superpower, is often left to do these jobs on its own.

Here's how Obama brought up international commitments to Afganistan in his speech, shortly after proclaiming that "America cannot insist that others follow the rules of the road if we refuse to follow them ourselves" and that force sometimes "extends beyond self defense or the defense of one nation against another"--clear references to Iraq.

I believe that force can be justified on humanitarian grounds, as it was in the Balkans, or in other places that have been scarred by war. Inaction tears at our conscience and can lead to more costly intervention later. That is why all responsible nations must embrace the role that militaries with a clear mandate can play to keep the peace. 

America's commitment to global security will never waiver. But in a world in which threats are more diffuse, and missions more complex, America cannot act alone. This is true in Afghanistan. This is true in failed states like Somalia, where terrorism and piracy is joined by famine and human suffering. And sadly, it will continue to be true in unstable regions for years to come.

The leaders and soldiers of NATO countries - and other friends and allies - demonstrate this truth through the capacity and courage they have shown in Afghanistan. But in many countries, there is a disconnect between the efforts of those who serve and the ambivalence of the broader public. I understand why war is not popular. But I also know this: the belief that peace is desirable is rarely enough to achieve it. Peace requires responsibility. Peace entails sacrifice. That is why NATO continues to be indispensable. That is why we must strengthen UN and regional peacekeeping, and not leave the task to a few countries. That is why we honor those who return home from peacekeeping and training abroad to Oslo and Rome; to Ottawa and Sydney; to Dhaka and Kigali - we honor them not as makers of war, but as wagers of peace.

In a way, Obama's entire speech can be seen as a justification of the coalition war in Afghanistan and as a pitch for a greater shared, international, communal devotion to enforcing right and preventing conflict across the globe. But this segment of his speech was the only part where he went right out and argued for not "leav[ing] the task to a few countries." It was not an overt pitch--but a coded, nuanced discourse on Afghanistan that fit within his broader vision of international norms and how war should be conducted.

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