Kim [Il-Sung] described his father as a young man consumed by patriotism who exhorted his schoolmates: “Believe in a Korean God, if you believe in one!” After the family moved to Manchuria, his father went to every service at a local chapel and sometimes led the singing and played the organ, teaching his son to play also. But this, insisted Kim, was just a chance to spread anti-Japanese propaganda.
By 1947, [Kim] had become the center of a personality cult, modeled on Stalin’s, in which he was pictured as wise, strong, compassionate—and energetic enough to involve himself in virtually every significant decision. He was reported to have supervised closely even the composition of the national anthem. Perhaps calling upon his experience as a church organist, he urged the committee involved to insert a refrain between the verses, to “improve the rhythm and harmony of the music [and] add to the solemnity of the song as a whole, and inspire the singer with national pride and self-confidence.” According to an official biography, “none of the poets and composers assembled there had thought of this until he pointed it out.”
—Bradley K. Martin, Under the Loving Care of the Fatherly
Leader: North Korea and the Kim Dynasty (pp. 16, 59)
Kim Il-Sung, the authoritarian ruler of North Korea for over forty years, started out as a church organist? Explains an awful lot, actually.
it seems implausible that none of the composers would consider that nationalistic pride should come from a national anthem! ah well, that is an interesting bit of back story.