SHENZHEN, China - North Korean leader Kim Jong Il left the family business in terrible shape.

Under his leadership over the last 17 years, almost 10 percent of his country's population, about 2 million people, died of hunger. North Korea developed nuclear weapons, but its people sank ever deeper into poverty and isolation, even while patron and next-door neighbor China charged ahead with its economic miracle.

His youngest son, Kim Jong Un, was only recently named to succeed him and is still in his 20s. He has before him what seems an impossible task for a baby-faced young man who just a decade ago was attending high school in Switzerland: Rescue a failed state, and perpetuate the family dynasty into a third generation.

"Kim Jong Il was the glue that held the system together," said Scott Snyder, a Korea expert with the Council on Foreign Relations. "We don't know how the system will respond in his absence."

"Everything could potentially change," said Shi Yinhong, a professor of international relations at Renmin University in Beijing. "The only person who had the experience and who held the exclusive power is gone."

Kim Jong Un was extolled Monday by North Korean state media as the "Great Successor" to his father, who was referred to as the "Dear Leader," and to his grandfather, North Korean founder Kim Il Sung. The young man, thought to be just shy of his 28th birthday, is the "outstanding leader of our party, army, and people."

But it's not nearly so simple. In what has the makings of a Shakespearean drama, the young man is likely to be overshadowed at least for a time by a powerful uncle, Jang Sung Taek. And initial indications are that North Korea may try to set up a more collective leadership.

Jang, 65, is married to Kim Jong Il's younger sister, Kim Kyong Hui. Jang spent three decades in the ruling Workers' Party, holding key positions in the military and secret police and running North Korea's special economic zones. Members of his own family also hold powerful jobs with the military.

In contrast, his nephew's resumé is thin. Kim Jong Un attended a German-language public high school in Bern, Switzerland, where he had been registered as the son of a North Korean diplomat. His classmates described him as crazy about basketball and computer games.

Until September 2010, when he was named a four-star general, he was almost entirely unknown to the North Korean public. Even the exact spelling of his name a state secret.

"Kim Jong Un has had only two years," said Shi. "It is not enough time to become crown prince."

Current and former U.S. officials are divided on what to expect from the relationship between Jang and the new leader. Chuck Downs, a former Pentagon and State Department official, said the younger Kim was likely to be a figurehead with Jang actually running the show. Downs said he has concluded from years of watching North Korea that Kim Jong Un is not nearly tough enough for the job.

"You don't go from a guy who tries to be friends with everyone at his Swiss boarding school, who befriends enemies of North Korea and puts a poster of Kobe Bryant in his room, to being the kind of ruthless person who rules North Korea," he said.

Current U.S. intelligence officials concur that Jang is likely to play an important role, but regard him as too cautious to try to seize power for himself. And the U.S. government assessment is that Kim Jong Un is indeed ruthless enough to rule.

Regardless, officials in North Korea are likely to emphasize order while the succession unfolds. The military appears to be taking a more prominent role. The announcement Monday of Kim's death was signed by the four different entities from the party, military, and people's assembly.

"A lot depends on whether the power centers of the regime coalesce around Kim Jong Un, or see this period of uncertainty as an opportunity to change the balance of power internally," a U.S. official said. "Those are very tricky calculations to make in an authoritarian society like North Korea."

The new leader is unlikely to get much help from his closest family. His oldest brother, Kim Jong Nam, was assumed to be the heir, but fell from favor after being arrested at Tokyo's Narita airport trying to sneak in under a fake passport to take his son to Disneyland.

Kim Jong Nam said last year that he opposed the "hereditary succession into a third generation."