Nativism is a policy to encourage native inhabitants' interests against immigrants' interests. This policy was established because native people believed that immigrants would distort the natives' cultural values. There were situations in which immigrants outnumbered native inhabitants and in this way, the different native people's movements tried to avoid cultural change.
There were some measures adopted against immigrants in terms of economy, culture and environment. For example, it was said that immigrants acquired jobs that should be given to native people as well as they did not pay the required taxes compared to their services' costs. Another aspect was that immigrants did not learn the language spoken in a specific community.
Nativism is a political policy which aims to promote the interests of native populations against those of immigrant populations. This policy includes the creation of restrictions to prevent a further influx of immigrants to their "homeland".
Some of the arguments nativist groups use to support their actions are that the government spends an important part of the budget in immigrant populations and that these groups do little in order to fuse with society but rather isolate themselves.
In a nutshell, the Korean War was a result of the Cold War. After WWII, the Japanese lost control of the Korean Peninsula which eventually was divided up between the US and the USSR. The line that divided the peninsula was named the “38th parallel.” The line that separated North Korea from South Korea.
The strategy of "containment" is best known as a Cold War foreign policy of the United States and its allies to prevent the spread of communism after the end of World War II.