Kim Jong Il, the enigmatic and combative man who led North Korea since 1994, died Saturday at age 69 while traveling by train across his isolated, poverty-stricken communist nation. A weeping state media broadcaster reported Monday that Kim died from "overwork" after "dedicating his life to the people," although the immediate cause of death was a heart attack. Kim had been in poor health for years, and was being treated for "cardiac and cerebrovascular diseases," according to the state-run KCNA news agency. North Korea has had only two leaders since its founding in 1948: Kim Jong Il, and before him, his father, Kim Il Sung. Now, South Korea has put its military on "emergency alert" out of fear that the loss of the North's "Dear Leader" could give way to dangerous instability. What will Kim Jong Il's death mean for the Korean peninsula? Here, four predictions:

1. One of Kim's sons will probably take over
Kim Jong Il's third son, Kim Jong Un, has been dubbed "the great successor," say Greg Botelho and Holly Yan at CNN, "indicating he would assume his father's post." But Kim Jong Un "is even more of an enigma than his late father was during 17 years of absolute power," says the Associated Press. He was only introduced as his father's likely successor — and a newly minted four-star general — a year ago. If he's going to have a smooth transition, Kim Jong Un is going to need the "longtime support" of his powerful uncle, Jang Song Taek.

2. But there could be a power struggle
Because Kim Jong Un is still in his 20s, he has had little time to "consolidate his power," says Patrick Edaburn at The Moderate Voice. I wouldn't be surprised if military leaders tried to muscle him aside. And even if Kim Jong Un "really is in complete control," says Max Fisher at The Atlantic, he's likely to "stumble." If he does, "military leaders worried about the country's stability may be tempted to intervene." That could be chaotic. Indeed, "the greatest threat Kim Jong Il poses in death, just as in life, is not that his state will commit an act of unprovoked aggression, but that it will collapse."

3. Kim's successor may create a crisis to solidify control
"Kim Jong Un is a pale reflection of his father and grandfather," the Heritage Foundation's Bruce Klingner tells Reuters. Kim Jong Il was groomed for 20 years to succeed his father, while Kim Jong Un is still something of a neophyte. He might need to provoke a crisis, such as a showdown with the U.S. or South Korea, "to prove his mettle to other senior leaders or deflect attention from the regime's failings." Fortunately, it won't take a war, says Allahpundit at Hot Air. "A limited provocation — like a new nuclear test, for starters — might be enough of a show of force to keep everyone at home in line."

4. Meanwhile, nuclear negotiations will be put on hold
Kim Jong Il's death "could put a brake on talks ultimately aimed at getting the secretive communist state to give up its nuclear weapons," says the Associated Press. Until the new leadership is in place — and shows it can survive — nobody will have the authority to negotiate with the U.S., "which retains about 28,000 troops across the border in South Korea." The only thing we know for sure is that North Korea now "enters months of intense mourning for the Dear Leader, and rising uncertainty."