SEOUL - Kim Jong-Il's sudden death puts the fate of nuclear-armed North Korea in the hands of a young dictator-in-waiting whose penchant for tyranny - or desire for reform - remain a mystery.
The death of the "Dear Leader" has raised cautious hopes that the country's third-generation dynastic succession could usher in a period of more benevolent and pragmatic leadership under his youngest son Kim Jong-Un.
Observers say the Swiss-educated basketball fan, described by the mouthpiece of the communist state as the "Great Successor", may be less suspicious of the West than his father, who died Saturday aged 69.
"This is a turning point for North Korea whose reins have been taken by a new generation," said Cheong Seong-Chang, a specialist in the succession issue at South Korea's Sejong Institute think-tank.
"His father was more ideology-oriented and seldom experienced capitalism.
Kim Jong-Un, who studied in Switzerland for four and a half years and saw a market economy, is likely to adopt a more pragmatic approach."
But experts also believe that it could be years before Kim Jong-Un, who is still in his late 20s, emerges from his father's shadow - if at all.
While the elder Kim was groomed for 20 years to take power from his father, who died of a heart attack in 1994, Kim Jong-Un has had barely three years and is expected to rely heavily on his aunt and uncle as mentors.
Despite Western calls for North Korea to follow in the footsteps of fellow pariah Myanmar and pursue political and economic reform, experts think the new leader is likely to stick to the Kim family doctrine, at least initially.
Indeed, North Korean state media said Tuesday that Kim Jong-Un was "at the vanguard of the Juche (self-reliance) revolution".
"There is unlikely to be any kind of breakthrough in terms of executing political and economic reforms," said Sarah McDowall, senior analyst at the economics and geopolitical risk consultancy IHS.
"Kim's near-to-medium-term priorities will be to win over the respect of the political elite and military, and bolster his image in the eyes of the North Korean public," she added.
A major worry is that the heir - a freshly minted four-star general - could put on a show of military strength to shore up his grip on power, inflaming tensions on the Korean peninsula.
"An attempt to show that he's a decisive leader - a powerful leader - through some kind of provocation is probably the biggest risk," said expert Marcus Noland at Washington's Peterson Institute for International Economics.
He said this could involve another nuclear test or a military strike on South Korea, which blamed the North for the sinking of one of its warships in March 2010 near the border with the loss of 46 sailors.
The North denied blame for the sinking but shelled a South Korean island in November 2010, killing four people.
At the time, analysts suggested those events were designed to boost the younger Kim's standing among North Korea's military command. South Korea has vowed to respond to any new cross-border shelling with air strikes.
Renewed sabre-rattling could be a way to distract public attention from chronic food shortages in a country where hundreds of thousands died in the mid- to late-1990s during a famine presided over by Kim Jong-Il.
A senior US diplomat last week held talks with top North Korean officials in Beijing to discuss the possible resumption of US food aid.
South Korean media have linked the meeting to a possible third round of bilateral talks aimed at reviving six-nation negotiations on North Korea's nuclear disarmament.
The North quit the six-party forum in April 2009, one month before its second nuclear test, and prospects for a resumption of the long-stalled talks have now been thrown into doubt.
"The question is, if the North Koreans go back to the six-party talks, will they be in any position to really negotiate or is this a government that will be too weak and insecure that they're unable to make concessions?" said Noland.