pretext to harm the state, introduce foreign forces, or harm the existing social order. North Korean anti-religion campaigns and contrary views It is very difficult for outside observers to know what has happened to North Korean religious bodies over the past 60 years due to the extreme isolation of the state. One interpretation has held that all open religious activity in North Korea was persecuted and eradicated after Kim Il-sung took power, only to be revived in the present as part of a political show. Another interpretation has held that religion survived and has genuinely been revived in the past few decades. Kim Il-sung criticized religion in his writings, and North Korean propaganda in literature, movies and other media have presented religion in a negative light. Kim Il-sung's attack on religion was strongly based on the idea that religion had been used as a tool for imperialists in the Korean peninsula. He criticized Christians for collaborating with the United Nations' forces against him during the Korean War, although he praised Christians who supported him. Accounts from the Korean War speak of harsh persecution of religion by Kim Il-sung in the areas he controlled. Prior to the war, the Christian population of the Korean peninsula was most heavily concentrated in the north; during the war, many of these Christians fled to the South. Some interpretations have considered that the Christian community was often of a higher socio-economic class than the rest of the population, which may have prompted its departure for fear of persecution. The large-scale destruction caused by the massive air raids and the suffering experienced by North Koreans during the Korean War helped foster hatred of Christianity as being the American religion. It was seen by many Koreans in the north as the religion of the imperialists. According to a study by Ryu Dae Young, however: Religion was attacked in the ensuing years as an obstacle to the construction of communism, and many people abandoned their former religions in order to conform to the new reality. On the basis of accounts from the Korean War as well as information from defectors, an interpretation has held that the North Korea was the Second state in the world state to have completely eradicated religion by the 1960s. Other interpretations have thought that they do represent genuine faith communities that survived the persecutions. An interpretation has considered that these religious communities may