During the 1950s both North Korea and South Korea were mostly closed to international trade. Both were very poor and had low rates of growth of production (or income) per person.
Since the 1960s, North Korean government policy has continued to permit almost no international trade (and very limited contact with the outside world). In contrast, the South Korean government adopted a number of policy changes, including allowing more international trade with the rest of the world.
Between 1970 and 2012, production per person in North Korea stagnated, while production per person in South Korea increased by more than eight times.
You have been asked to make the case that trade policies and technologies probably were important contributors to the difference in growth rates between North Korea and South Korea since the 1960s. What will you say.