First, a disclaimer! Yes, I am Korean, but I have lived in America since I was 2 and have never had dog meat and do not intend to. As such, I have tried to write from an unbiased viewpoint. Feel welcome to leave any comments, rebuttals, etc.
Animal rights activists and Western countries have been all riled up about Koreans eating dog meat. A dog show refused sponsorship from Samsung because of the issue, when the 1988 Olympics came, Korea was pressured into banning it, and FIFA had also pressured Korea about the issue. Read about it here. What had always confused me was what was so different about dog meat than other meat, besides the fact that it wasn't eaten in the West. Does India get angry and refuse to go to countries because they eat beef? It might be taboo in India, but not in other countries. Additionally, the animal rights activists cite 'excessive cruelty.' From what I've picked up based on PETA's propaganda machine, other animals aren't treated especially well, either. And about the whole livestock-versus-pet thing, I just don't get it. Example: fish. Goldfish and other types of fish are kept as pets, but we eat other kinds of fish. The dogs used for meat in Korea is different from the types of dog used for meat.
In conclusion, I just don't get what's so special about dog meat that makes slaughtering dogs cruel, while slaughtering chickens, cows, and pigs en masse is not. Hm. Sounds like cultural imperialism to me.
Edit: An opinion better written than my own.