Openly stating cooperation and co-existence as a goal of the foreign relations policy towards North Korea, and reaffirming publicly that reunification with, and absorption of, North Korea is not, in any way, part of South Korea's political agenda, it can only serve to ease tensions between the two countries. Making these statements publicly, while also declaring that any armed provocation by the North will not be tolerated, is probably the most sensible approach that South Korea can take in the current situation.
Despite North Korea's isolationist foreign policy, the South Koreans need to continue to follow their Sunshine Policy towards North Korea. If the North Koreans cut ties to South Korea, North Korea would be almost totally isolated. It is important for the two countries, with a common language and culture, to have ongoing relations.
North Korea always seems to be looking for any reason to renew their war with South Korea. The sunshine policy helps keep the peace between the two nations, and also could possibly pave the way for reconciliation between them one day. It also gives South Korea a slight upper hand, as they can say that they tried as hard as possible to maintain the cease fire, in the event that another war starts.
The principle of the sunshine policy is to support peaceful coexistence between North and South Korea, rather than having one side try to take the other over. Throughout history, it's been shown that cultures that are different from each other tend to start wars to take over the other or their land, rather than coexist with the mixing of cultural ideals. It is unlikely that North and South Korea's cultures would ever mix well, so having a treaty for a peaceful, but separate, coexistence seems to be the best option.
South Korea's sunshine policy, which lasted more than a decade before the country recently ended the policy, was a reasonable approach to living with their unreasonable neighbor to the north. The policy recognized the fact that North Korea not only was largely immune to pressure from South Korea, but also tended to have disproportionate, belligerent, and irrational reactions to such pressure. The sunshine policy dealt with the situation in two important ways: by avoiding actions and policies that North Korea could use as an excuse for belligerence. And, it tried to establish business and cultural connections that would work over time, to grow a constituency within North Korea to normalize relations with other countries.
South Korea has attempted to improve relations with North Korea by having a no-conquer attitude, warmer negotiations, and greater communications. These types of attempts at greater outreach between the two countries resulted in some well deserved international acclaim and recognition, prior to the more difficult period of the last two years.
I feel that South Korea's sunshine policy toward North Korea is sensible because it delays active military warfare, which reduces the chances of a military conflict in the region. This is because if they wait long enough, North Korea will either collapse as a state or a sensible leader will gain enough power to make such a conflict unlikely.
At its most basic level, the sunshine policy is South Korea being overly nice and encouraging to North Korea. By adopting this policy, South Korea essentially ignores all of the human rights violations in North Korea. And by ignoring them, they are indirectly supporting it. The sunshine policy won't lead to reunification or the betterment of the North Korean people. They would be better served to take a hard line.
The idea behind the "Sunshine" Policy was to have peace, cooperation and negotiation with North Korea while still maintaining security. This is a noble idea but has not always been easy in part because of North Korea's suspicions that South Korea is wanting to take it over and South Korean leader's tendency to use this "Sunshine" policy to its own advantage. Despite these problems, the "Sunshine" policy prior to 2008 seemed to help both nations to live in harmony and did pave the way for some much needed visits of seperated family members in North and South Korea.
North Korea has uniformly, to an extent, attempted to bring itself into the international scene. It has toned down anti-U.S. propaganda, attempted to implement a limited free market, and courted many international corporations to invest within itself. The best way for South Korea to defend against North Korea, which has the capability of razing Seoul to the ground within hours, is not military, but diplomatic and economic.
There are two parties in South Korea, the Conservative and Liberal Parties. The Liberal Parties are still Pro-North Korean, which proves that when we had a Liberal President, they were REQUIRED to help North Korea. If we didn't give them any aid, they would not be as powerful as they are now. It was a mistake on South Korea's part, but the president didn't do it for the sake of the country.
In order for a coordinated policy of rapprochement to be effective, the other side must be not only responsive to it, but also capable of logical reasoning. The Kim Jong Il regime is incapable of logical and rational policy formation, as evidenced by its erratic behavior throughout its reign. Without the willingness to entertain normalization of relations, and the rationalism to accept the benefits of such policies, any attempts by the South to woo the North will be fraught with peril, and most likely will achieve little success.
Kim Dae-jung's Sunshine Policy is well-intentioned, but without true cooperation and compromise, it has remained something that looks good on paper. North Korea has proved itself to be hostile and uncooperative at every turn, when the two groups try to come together. They have not allowed a significant amount of families to be reunited, and the ones they have allowed to meet are closely monitored.
The softening of economic policy towards North Korea, represented by the "sunshine" policy, would only have worked if there was an actual desire within the North Korean government to move towards peace and reconciliation. Unfortunately, the existence of the North's extremely authoritarian regime depends on antagonistic foreign relations. Without the "bogey man" of South Korea and its allies, the North's military state loses its reason to exist. Still, the plan might have borne fruit if North Korea's military regime did not have strong material support from China, making a popular uprising all but impossible. As such, the "sunshine" policy did little more than goad North Korea's government to greater provocations, including the development of nuclear weapons and long-range missile technology.
The policy's focus on assistance and cooperation initially appeared more likely to create an atmosphere conducive to change than the former isolationist policy. However, as implemented, there was no reciprocity but a one-way street from the south to the north. The policy also hasn't reduce military tensions. Incursions have increased as has North Korea's store of weapons.
The sunshine policy implemented by South Korea in an attempt to facilitate reconciliation with its neighbor North Korea was ill conceived. North Korea lead by Kim Jong Il is a dangerously unpredictable country. The leader of this country has an intense hatred for the democracy represented by the South. Reconciliation and negotiation with North Korea would be on their terms and result in few benefits.