Kim Jong Il, North Korea's supreme leader, took new steps Tuesday to ensure that his family remained in charge after his death, but the biggest leadership shuffling in a generation has so far produced more political intrigue than signs of real change in North Korea, one of the world's most isolated nations. Kim elevated his sister and a close friend to the highest military ranking and had his youngest son and heir apparent, Kim Jong Un, made a member of the Central Committee of the ruling Workers' Party. The promotions came a day after the younger Kim was also made a four-star general and seemed aimed at ensuring a dynastic succession that would give Kim Jong Un, thought to be in his late 20s, time to solidify his power. The elevation of the completely unknown Kim, and hints that other members of the extended Kim clan will exercise power behind the scenes in a kind of Communist regency, add to the uncertainty about North Korea. The country appears to have mostly abandoned its incipient economic reforms and has declined to enter new international talks about its nuclear weapons program, leaving its neighbors and the United States alarmed about its intentions. Few analysts claim to fully understand the inner workings of the North Korean military or the Kim dynasty. But many who watch the country closely say they see few signs that succession will produce a stable, credible leadership that is, at least initially, confident enough to engage with the outside world or to steer resources to economic development rather than the military. Some analysts predict that new leaders may feel compelled to prove their nationalist credentials by engaging in provocative actions that could worsen tensions with South Korea and Japan and their main ally, the United States. 'The question now is whether they will do dangerous things like the Cheonan or something else to hold the regime together,' said Victor Cha, director of Asian studies at Georgetown University. 'They were already unstable as it was, and this succession issue makes them even more unpredictable.' In the most destabilizing situation, an internal power struggle could also lead to the collapse of the government. But many observers discount that possibility, largely because of the support of another neighbor, China. The reasons behind the elevation of Kim Jong Il's sister, Kim Kyong Hui, and Choe Ryong Hae, a lifelong friend of the Korean leader and a member of his inner circle, along with the promotion of Kim Jong Un, are uncertain. 