|North Korean leader Kim Jong-un|
According to Dong-A University professor Kang Dong-wan, who recently acquired the book, this shows North Korea still has a deep sense of distrust and hostility toward the United States and South Korea.
The nursery rhyme book included phrases mocking the two countries. The 190-page-long book, named Chukposeong, included about 130 poems aimed at enhancing the North's internal propaganda.
One poem contained such phrases as "[Americans] will be burned to death even if they tighten sanctions and pressure [against the North]."
This shows the North was focused on instilling a sense of hostility against both the South and the United States in children even at a time when North Korean leader Kim Jong-un was expressing his willingness for peace and denuclearization of the peninsula last year.
Despite the outward peace gestures, the book also indicated that North Korea continued to brag about its military prowess internally. Another noteworthy phrase from the book included: "The North's ballistic missiles are the best."
In another poem from the book, the North mocked South Korean President Moon Jae-in, calling him an American version of Korea's traditional Sapsal dog.
President Moon held three summits with the North's young leader last year when the inter-Korean peace momentum reached its peak.
The rare reconciliatory mood in inter-Korean relations, however, started falling into uncertainty in the wake of the breakdown of the Hanoi summit in February between U.S. President Donald Trump and Kim Jong-un.
Starting this month, the North resumed its military provocations by test-launching missiles.