New York (CNN) -- The skirmish between North and South Korea over Yeonpyeong, an island in the disputed zone between the two sides, has brought new danger to a standoff that has been escalating for more than two years. It happened just two days after North Korea revealed a sophisticated uranium enrichment program to three American visitors from Stanford University, and in the midst of its leadership transition from Kim Jong Il to his son, Kim Jong Un. How can the international community respond in a way that will deter North Korea without pushing the situation into all-out war? None of the options is particularly attractive: Strong sanctions and displays of force have already been tried, and failed to stop the latest attack. Military retaliation could easily escalate into war involving the Koreas, the United States and possibly China, with devastating consequences.
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Charles Armstrong says North Korean attack confronts the world with difficult options
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Sanctions have failed, military action could be disastrous; talks the least bad choice, he says
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North Korea may be trying to show it's a force to be reckoned with, Armstrong says
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Talks could reveal what it will take to get Pyongyang to abandon nukes, he says
But for now, a nuclear @placeholder is a reality we must deal with.