North Korea isn't close to having a nuclear bomb it can use on the United States or its allies. Instead, Hecker said in a posting on Stanford University's website, "it wants to hold U.S. interests at risk of a nuclear attack to deter us from regime change and to create international leverage and diplomatic maneuvering room."
Associated Press writers Kim Kwang Hyon in Pyongyang, North Korea; Foster Klug, Hyung-jin Kim, Youkyung Lee and Sam Kim in Seoul, South Korea; and Yuri Kageyama and Malcolm Foster in Tokyo contributed to this report.
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