The Second Great Awakening, spread religion through revivals and emotional preaching, sparked a number of reform movements.
Nationalist ,eg Kwame Nkrumah,led a peaceful campaign of strikes and boycotts against British holdings..
German-language books were burned, and Americans who spoke German were threatened with violence or boycotts. German-language classes, until then a common part of the public-school curriculum, were discontinued and, in many areas, outlawed entirely.
The major factor is that they had different ideologies.
While the United States(US) believe in capitalism, where people should have freedom on their daily basis,such as trading,politics, and speech. It encouraged a free Market. While Soviet Union(USSR) took up communism, which controlled the general market and people do not have the freedom of speech and politics.
Both had the fear of the spread of one another's ideology especially US,was worried that communism would spread to the western Europe.Thus causing the tension and much suspicion between the two nations,leading to Cold War.
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