If I remember correctly, North Korea is called "北朝鮮{きたちょうせん}" in Japan? But, I think "朝鮮" might actually be written in Katakana?
Anyway, given that "朝鮮" was Japan's colonial name for (all of) Korea, shouldn't it be named something other than "北朝鮮"? (Personally, I have no opinion about this). Surely, that is why South Korea is now 韓国{かんこく} and not "南朝鮮{みなみちょうせん}? I mean, no matter how strained (or non-existent) Japan's diplomatic relationship with North Korea might be, don't the South Koreans object to the name "北朝鮮" (because it conjures the history of colonial Japan)??
primary reason I asked the question:
I've always thought that "朝鮮" has a negative connotation in Japanese daily conversation, yet South Koreans (as far as I know) don't object to North Korea being called "北朝鮮" even in NHK broadcasts. That is the only reason I asked the question.
The answers I got are great. I understand now.