What is the general attitude in South Korea towards their cousins in the North? Do they have nightmares of North Korea suddenly pulverizing Seoul with an artillery bombardment and sending their army marching south? Or do they perhaps see Kim Jong-il and the North Korean state as basically harmless and are more or less indifferent towards it? I'm sure there are people who subscribe to either of those views (as well as many others) but what is the majority opinion?
On a related note, how are North Korean defectors seen in the South? Are they considered uneducated peasants, opportunistic job-stealers, benighted peoples struggling to be free, or what have you?
The Korean knows that you are a frequent contributor on the comments, so he apologizes for having your question finally answered after sitting in the inbox for 8 months. And the line is only getting longer.
North Korea issue is one of the hottest political issue in South Korea, and everyone has an opinion about them. Your description is not very far off, but the opinions are generally divided into three groups. The divide tends to be along the generational lines.
First set is a mixture between rage and fear. This group tends to be older Koreans who personally experienced the war. (Usually mid-50s and above.) Korean War, as all modern wars are, had very high number of civilian casualties. This is especially the case from North Korean-occupied places, where the richer people were literally taken out and shot by the People's Army in the hopes of creating the proletariat paradise. Because North Korea was initially victorious, many people in South Korea were killed as well.
For people who have seen this event, a war is a very real possibility at any moment. (It does not help that there were many assassination attempts and terrorist attacks against South Korea by North Korea up to late 1980s.) North Korea--personified as Kim Il-Sung and Kim Jong-Il, instantly turned everything they knew into rubble.
Therefore, they set a very hard line against North Korea. It's not that they hate North Koreans; it is more precise to say that they hate the North Korean government/dictatorship. Since dealing with North Korea necessarily means dealing with the North Korean government, they generally would not deal with North Korea, period.
The second group is relatively favorable to North Korea. They feel that the division in Korea should not continue, and would try to engage with North Korea as much as they can. These tend to be in the younger generation (30s~40s), those who feel the tragedy of the division through their parents but did not see the war themselves.
Furthermore, they feel that the danger of communist takeover has been exaggerated and manipulated, which is certainly true to some degree. One of the ways in which military dictatorship in South Korea justified their existence was that without a strong (= dictatorship) government in South Korea, the dictatorship in the North would obliterate the South and take over. Using this excuse, the military dictatorship suppressed and oppressed legitimate labor and democratization movements in South Korea. Since the younger generation was largely the driving force behind democratization, they often just roll their eyes at the mention of North Korean threat, much like the way liberals in America roll their eyes at the mention of "the necessity for national security."
These people do not have much qualms about dealing with North Korea, even though it means it has to legitimize the dictatorship in the North by talking to them. After all, it is the only realistic way of reducing the military tension on Korean peninsula and bring about the remotest hope for reunification.
As you might have noticed, the "dealing with North Korea" part is a real spark point between these two groups -- let's just call them Hawks and Doves as a shorthand. For example, Doves wanted to set up a cruise tour of a famous mountain in North Korea, even though the North Korean government would control every aspect of it and charge higher-than-market price. For Doves, getting North Korean government out of its hole, and getting South and North Koreans to actually meet each other, would be an achievement in and of itself. For Hawks, the money is sure to fill the coffers of Kim Jong-Il and enable him reign longer, which cannot be tolerated.
For the last ten years, the South Korean administration leaned towards Doves. It did achieve certain important things, such as reducing military tension, regular communication between governments, and eliciting better-than-before openness from North Korea. However, it has been severely criticized for allowing North Korea to have nukes despite giving so much aid and money. (It can be disputed whether the aid and money truly amounted to much given the strength of South Korean economy, but it was definitely much in the Hawks' mind.)
So as of now, there is almost an even split among Hawks and Doves in Korea. But the third, very important group still remains: the group that does not care. This is the group that grew up without seeing any of the scars of the Korean War, or any memory of North Korea being the same country.
The Indifferent group simply does not care about North Korea. Having lived under the "threat" of North Korea for all their lives but seeing no death or destruction, they are not moved by the possibility of war like Hawks. No longer having anything in common with North Koreans, they do not recognize North Koreans as brothers like Doves.
Right now, this group is politically inactive because they tend to be fairly young -- late 20s, tops. But this group has a strong potential to change the political landscape of North-South relation in the next 10 years or so. And that is the Korean's biggest concern about the North-South Korean relation in the future: at some point, South Koreans are going to stop caring about reunification. And one of the greatest historical injustice created by the colonialism of the 20th century will be allowed to live on.
What do South Korean people think about North Korean defectors? At this point, the number is too low to truly gauge. Up to 1980s, North Koreans who escaped to the South were headline-makers, partially because of their rarity, partially because of the South Korean dictatorship's necessity to advertise its superiority. But now we arrived at a point where there small but steady stream of North Korean defectors, so they longer really make the news. But the future will probably hold something unpleasant for those people, if the South Korean treatment of Korean-Chinese is any indication.
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