News reports indicate that North Korea may be preparing for a nuclear test, potentially scheduled to coincide with President Obama's visit to South Korea this week. The North Korean foreign minister warned Tuesday that Obama's trip could "escalate confrontation and bring the dark clouds of a nuclear arms race," prompting speculation that the impulsive young leader of the North, Kim Jong Un, is again crying out for attention. Typically, experts and government officials refer to these outbursts and nuclear or missile tests as "provocations," which are followed by sanctions, tensions and -- it is hoped -- a return to diplomacy. But by now, it should be obvious that while North Korean behavior appears cyclical ("there they go again"), Pyongyang is on a clear, linear  path to developing nuclear weapons and the means to deliver them on target in Japan and eventually the United States.
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North Korea may launch nuclear test to coincide with Obama's visit to South Korea
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Writers: If it's a more serious provocation, it could signal an uptick in nuclear capability
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They say strong U.N. sanctions necessary to stop a possible march toward nukes
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Writers: U.S. must strengthen ties with S. Korea and Japan and build up its deterrent system
In December 2010, the U.S., Japan and South Korea came very close to issuing a joint collective security statement, declaring that an attack by the North on any of us would be an attack on all of us, after the North sank a South Korean vessel and shelled civilians on a @placeholder-held island.