According to ''New Focus International'', the cult of personality, particularly surrounding Kim Il-sung, has been crucial for legitimizing the family's hereditary succession. The control the North Korean government exercises over many aspects of the nation's culture is used to perpetuate the cult of personality surrounding Kim Il-sung, and Kim Jong-il. While visiting North Korea in 1979, journalist Bradley Martin wrote that nearly all music, art, and sculpture that he observed glorified "Great Leader" Kim Il-sung, whose personality cult was then being extended to his son, "Dear Leader" Kim Jong-il.