Over the last few years more details have leaked about South Korean and U.S. plans for what they will do when the government in North Korea collapses. This sort of planning has become a lot more detailed in the last decade and more attention has been paid to discovering the “unexpected” situations before troops on the ground have to deal with them.
Four years ago South Korea made public that if North Korea attacked, South Korea was prepared to go north and do whatever needed to be done. This is no surprise to those who have been observing the South Korean armed forces development since the end of the Cold War in 1991. During the same time the North Korean armed forces have declined because of a bankrupt economy and no money for replacing obsolete equipment or for training. Meanwhile, the booming economy in the south led to the growth of domestic arms industry and the re-equipping the South Korean military with modern, and locally made, weapons.
South Korea has nearly completed a 15 year plan to transform their army from a large force of conscripts, to a smaller, high tech force containing many more, higher paid, volunteers. The south sees this, the "American approach," as superior and proven. Over the last two decades South Korea has developed, and produced in large numbers, their own versions of the U.S. M-1 tank (the South Korean K-1 and K-2), the U.S. M-2 Infantry Fighting Vehicle (the South Korean K-21), the U.S. M-109 self-propelled 155mm howitzer (the South Korean K-9), and much more. South Korea used the American equipment as models and then built on that. South Korea also manufactures an Aegis destroyer (the KDX III class), a new class of frigate (FFK), and a light fighter/trainer jet (the T-50). All this provided South Korea with a decisive military edge over its aggressive northern neighbor.
The southern generals believe that the North Korean military is in terminal decline. Over a decade of famine and extreme poverty has caused severe reductions in maintenance and training in the North Korean military. This has sharply lowered the combat capabilities of the northern force. Corruption and poverty has increased corruption and insubordination up north.
In response to all that, South Korea staff officers quietly began drawing up plans on how they would move into the north. This would happen either in response to an attack from the north or a collapse of the communist police state government up there. In either case it would be a combined military and humanitarian mission. Wargaming out the many possible scenarios made it clear that intelligence would be a major problem because North Korea has been a closed society for 60 years and the U.S. and South Korea have very few informants up there. This has led to several highly classified programs for quickly getting intelligence operatives on the ground up there and keeping them alive. There are also several new tactics for using food and other supplies to quickly win over the North Korean population.
Although most North Koreans now know their government has been lying to them about the outside world, and that life is much better in South Korea, because North Koreans are brainwashed from birth, some will still not welcome the southerners as liberators. South Korea is not making this stuff up, as they have over 24,000 North Koreans who escaped to South Korea, most of them in the last decade. These North Koreans give details about how people think and are likely to react during a collapse up north. Given the food and other shortages up there since the 1990s, any aid will be much appreciated and likely fought over. South Korean troops have to be combat ready but also prepared for relief work and peacekeeping.
There are far fewer roads in the north than in the south and less infrastructure in general. There is also the possibility of Chinese troops coming in as well. China has apparently made plans to annex North Korea, or set up a very pro-China government. But while that is being sorted out the more immediate needs of caring for North Korean civilians and fighting any die hard North Korean soldiers has to be attended to, as well as securing nuclear and conventional weapons storage areas.
While the collapse of the North Korean government may lead to war with China, it will definitely lead to one of the most challenging peacekeeping operations ever.