SEOUL — One family secret can hide another. A few drops of poison spilled in an airport terminal has shed some light on the fratricidal struggles that stir Pyongyang's communist dynasty.

It's been a month since Kim Jong-un's half-brother was poisoned with a VX nerve agent in the Kuala Lumpur airport, and yet mystery still surrounds a murder that could be fodder for a John Le Carré novel. All eyes are turned toward the North Korean Supreme Leader: Intelligence services in Seoul say he is the one who issued the order to kill his elder sibling and potential rival.

Kim Jong-nam — "Pyongyang's bastard," the eldest son whose mother was the late Kim Jong-il's mistress — may have been doomed the moment his younger half-brother ascended the throne. But in the heart of the Hermit Kingdom's capital, another enigmatic family member lurks in the young leader's shadow. And as high-ranked defectors and North Korean regime experts in Seoul asserted to Le Figaro, this sibling one day could turn into a much more tangible threat than the now late half-brother who was exiled in Macau.

This family member is a woman, as discreet as she is powerful, who would be whispering in the last red prince's ear.

This family member is a woman, as discreet as she is powerful, who would be whispering in the last red prince's ear. "North Korea's people have never heard of her, but all the clan members know about her existence. She plays the role of a shadowy counselor for her brother," says Lee Yun-jeol, who was a former North Korean scientist and who now runs the North Korean Strategy Information Service (NKSIS) and counsels the military intelligence services in Seoul.

Clan solidarity

The name of this mysterious 40-year-old woman, whose date of birth and face remain unknown, as no photograph of her has ever been revealed, is Kim Sul-song.

She is the current dictator's elder half-sister, born from the only official wedding contracted by their late father in the 1970s. The marriage with Kim Young-sook — the daughter of a general who was highly respected in the regime's ruthless social hierarchy — was blessed by Kim Il-sung, the regime's founder. The propaganda even put the spotlight on this wedding for a while.

The "Dear Leader" quickly neglected his wife but was enchanted by his offspring who was rumored to be of great beauty. According to South Korean daily Chosun Ilbo and based on an anonymous defector's testimony, the young woman with long black hair studied literature at the prestigious Kim Il-sung University and then in Paris, in 2005. As an adult, she dressed in the uniform of the Korean People's Army while accompanying her aging father on his travels in his armored train as far as Siberia.

Since the death of Kim Jong-il in December 2011, Sul-song seems to have worked her way to the top with the ascension of her half-brother Jong-un, who was appointed successor by their father at the end of his reign.

kim il sung jong il north korea propaganda

Portrait of Kim Il-sung with his wife Kim Jong-suk and son Kim Jong-il — Source: Mark Fahey/Wikimedia Commons

"She extended her influence in a unprecedented manner. She is the second most influential person in the regime," says Cheng Seong-chang from the Sejong Institute, a top expert of the family intrigue. Cheng adds that Sul-song has been given a key title in the Workers' Party of Korea: vice president of the central committee, in charge of the organization — further proof of her spectacular ascent.

Kim Sul-song is believed to be 10 to 13 years older than her dictator half-brother. Indeed, in the North Korean culture marked by Confucianism, age and blood offer precedence. She was also born from an official marriage — an advantage that Jong-nam didn't have — and which provides her with a dynastic legitimacy.

The absence of any official record about the enigmatic Sul-song reflects the difficulties for the world's intelligence services, including the CIA, to decipher the North Korean "black box." In front of these murky secrets, caution is necessary but rumors endure. "Nobody knows exactly what's going on within this family. I'm suspicious about anyone who spreads any information," says Andrei Lankov, professor at the Kookmin University.

Can Sul-song also wind up being seen as a danger for her half-brother? And even threaten his supreme authority?

Still, Thae Yong-ho, the highest ranked diplomat to have fled North Korea, confirmed Kim Sul-song's existence in a conference in Seoul last January. The former number two of North Korea's embassy in London, who got out in August with his family, had the honor of taking the dictator's brother Kim Jong-chol incognito to an Eric Clapton concert.

The experienced diplomat never met Sul-song, but he believes that she and her husband are the ones responsible for the cabal that led to the brutal execution of the dictator's uncle Jang Song-taek in 2013, in order to claim his position as the regime's number two. This bloody rivalry aimed at recovering the dynastic legacy of the "Mount Paektu lineage" by brutally eliminating this "patched piece" of the family. [Chang Song-taek was married to Kim Kyong-hui, the daughter of Kim Il-sung.]

Can Sul-song also wind up being seen as a danger for her half-brother? And even threaten his supreme authority?

Kim Jong-un has seemingly established an absolute power that was on stage last May during the 7th Congress of the Workers' Party of Korea, when the heir triumphantly concluded the dynastic transition sequence that started four years ago. This was a tour de force for the young leader, who seems to have benefited from the precious support of his big sister backstage.

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Photo: Chris Jung/ZUMA

This clan solidarity fully holds at a time when the country is challenging Donald Trump's America as well as his Chinese ally by multiplying nuclear and ballistic tests. "Right now they are standing together as one because the international situation is tense. But if a crisis was to start, she might become a rival," Lee Yun-keol estimates.

Indeed, some apparatchiks are concerned about the fiery marshal's atomic program. They fear the unpredictable new man in the White House might order a destructive U.S. strike in return. And most of all, the international — and now Chinese — sanctions are depriving some officials from profitable earnings supplied by the cross-border trade with Beijing. The suspension of coal imports that China enacted last February is still fueling these concerns.

"Kim Jong-un is in a difficult position because of these sanctions and the increasing pressure from China. The party's congress was the height of his power, but ever since, his influence has decreased. In this context, Sul-song can become a danger for him," Cheong says.

Unprecedented purges

To establish his authority, the chubby heir created a vacuum around him with brutal purges that have no precedent since the 1950s, according to Lankov. "He wants to show to the old officials who's in charge. He holds undivided power. But it's too much, and the violence of his methods is actually creating the conditions for a plot to arise," the Russian historian says.

While his grandfather relied on "reeducation" of the Maoist type, giving some perspective to the purges' victims, his grandson has opted to execute or put away several senior officials, which has spread fear among those at the top.

He wants to show to the old officials who's in charge. He holds undivided power. But it's too much, and the violence of his methods is actually creating the conditions for a plot to arise.

But this strategy of terror doesn't seem to undermine the leader's popularity among the majority of North Korea's 23 million inhabitants.

The world's most isolated country actually benefits from an improvement of living conditions thanks to a return to economic growth — boosted by the liberalization of agriculture enacted by Kim. "The markets are now free and the population profit from it," Lee Yun-jeol notes. The food situation has clearly improved since the famine of the 1990s, even in rural areas. A new merchant class is even emerging in big cities and in the border region with China. That's not enough to start a revolution.

Danger would rather come from the top. The intrigues of the court in Pyongyang — protected by the propaganda's impenetrable curtain — elude both the population and the outside observers.

But Kim Jong-nam's murder as well as Sul-song's enigmatic role shed some light on the potentially destabilizing factor of the rivalries left by the late Kim Jong-il inside the clan.

"He was a ladies' man with a preference for women of a lower social standing. He never ranked his lineage, which led to this current mess. The Ottoman Empire faced that exact same problem when it was threatened by the intrigues of the harem," Lankov explains.

Therefore, the young Supreme Leader, who was raised in Switzerland, could risk seeing other "bastards" born from different relationships as potential rivals who threaten his authority. That reality actually tempers the aura of power he has created and that has been put forward by the propaganda and reported by the international press.

"In reality, North Korea is run by a clan. Kim Jong-un is its symbol and holds the reins of power. But he has to take into account the vision of the other members of the family," Lee says. Perhaps there is no one's vision that counts more than that of his shadowy elder sister.

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