Reuters When Defense Secretary Leon Panetta visited US troops in South Korea in October and told them that they were on “the front line,” it was clearly a rhetorical flourish meant to show appreciation for the 28,500 American forces theoretically in firing range of the North. But less than two months later, North Korean leader Kim Jong-il's death has raised the possibility of true instability on the Korean peninsula. And rather than speaking with colorful bravado, US officials have been at pains to avoid doing or saying anything that could escalate tensions or create the perception of looming conflict. Indeed, Secretary of State Hillary Clinton Monday went so far as openly rooting for a smooth handover of power as Kim's son, the untested Kim Jong-un, prepares to take over. The United States has an interest in “a peaceful and stable transition in North Korea,” she said. Expect more messages like that in the coming days, and no overtly muscular moves by the Obama administration toward the reclusive state which has twice tested nuclear devices. “The goal is not to create chop in the water, to allow the transition to occur,” one US official told Reuters, speaking on condition of anonymity. A smooth transition that allows a third generation of North Korea's ruling dynasty to take power appears to be the least bad of many undesirable options for Washington, one that leaves hope for further diplomatic engagement over the country's nuclear program. Other options include terrifying scenarios like collapse of the North Korean state, which could flood neighboring China and South Korea with refugees and send economic ripples across Northeast Asia. Alternatively, a power struggle within North Korea's military and political elites would heighten the risk of conflict between North Korea and South Korea, Asia's fourth largest economy, that could drag in the United States. Despite the high stakes, Washington is largely on the sidelines when it comes to political developments within the North Korean state, where it has no embassy, limited contacts and few insights into the inner circles of power. That is one reason analysts believe it is important for Washington to work with China, the North's closest ally, which Monday expressed confidence the North would remain united. The US military, for its part, appears to be taking a wait-and-see approach that reflects caution at an uncertain moment for security on the peninsula. __