Heirs to the Kingdom : A recently leaked document suggests a brewing succession struggle in Pyongyang.(North Korea)(Illustration)

For the experts who ponder North Korea's future, reading tea leaves is part of the job description. But soap bubbles? Suds were among the clues contained in a cryptic, 16-page internal military document leaked from North Korea and published in February in the South. In it, a beatific woman described only as Omonim--or "Respected Mother"--displays boundless compassion for Pyongyang's massive Army. She acknowledges her country's "difficult" situation and asks soldiers if their soap ration is sufficient. The document calls her "the most faithful of the faithful, who devotes herself to our beloved supreme commander," meaning North Korea's reclusive "Great Leader," Kim Jong Il.

The subtext, in case you missed it, is a simmering North Korean power struggle. That's clear when the missive is decoded: Omonim, analysts agree, must be Kim's own wife. He's had two or three--depending on how one counts-- but from the context Respected Mother is alive and at his side today. Thus, she isn't the woman who bore the Great Leader's eldest son, an actress believed to have died in exile in Moscow last year. Conclusion: Kim has elevated his current paramour, the former folk dancer Ko Young Hui, to Respected Mother status in an effort to prepare their 22-year-old son, Jong Chol, to inherit the world's last Stalinist dictatorship.

The Kim brothers have been on a collision course since the elder, Jong Nam, was detained while attempting to enter Japan ("to go to Disneyland," he told immigration officials) in 2001. Their sibling rivalry, now public after months of whispering, adds a caustic new variable to the unfolding nuclear crisis on the Korean Peninsula. Last week Pyongyang tested a shore-launched cruise missile to mark the inauguration of South Korea's president. One day later the North restarted a nuclear reactor at Yongbyon, a complex mothballed in 1994. "This is not the time to be worrying about which son should take over," says Katsumi Sato, director of the Modern Korea Institute in Tokyo. "Once the U.S. and the rest of the world turn their eyes [from Iraq] to Pyongyang, the Great Leader will need to worry about his own a--."

The brewing feud illustrates a fundamental truth about North Korea: behind its grotesque communist veneer, the country --remains gripped by a quasi- religious personality cult that is, above all, Confucian. Built by founding patriarch Kim Il Sung, a protege of Soviet dictator Joseph Stalin, it allowed him to hand power to his son, Jong Il, in 1994 in the communist bloc's first and only hereditary succession. As the elder son today, Jong Nam has a claim to the throne even if his father disapproves. "For the last 10 years many party and military officials have supported him as heir apparent," says a South Korean diplomat in Tokyo. "If the father suddenly chooses the second son, there will be a power struggle and possibly a coup."

Pyongyang watchers have worked hard to piece together what little is known about the two rivals. Jong Nam, 32, was a spoiled, ill-mannered boy whose stint at an elite Moscow boarding school was cut short reportedly because "the toilets were too dirty." He then spent two years at an international school in Geneva, attended Kim Il Sung University in Pyongyang and later took a high post inside the Korean ...