What happened in China in 1948 and how did it affect the US?

In 1948, China was embroiled in the final stages of the Chinese Civil War between the Nationalist government of the Republic of China (led by the Kuomintang or KMT, under Chiang Kai-shek) and the Communist Party of China (led by Mao Zedong). However, the most significant event that affected the US and the global geopolitical landscape occurred shortly after, in 1949, when the Communist Party eventually triumphed.

Throughout 1948, there were a series of major offensive campaigns by the Communist forces, such as the Liaoshen, Huaihai, and Pingjin campaigns, which led to significant victories against the Nationalist forces. The outcome of these battles heavily swayed the balance of power in favor of the Communists.

The transition of power in China from the Nationalists to the Communists in 1949 (officially the founding of the People's Republic of China was proclaimed on October 1, 1949) had profound long-term implications for US foreign policy. Prior to the Communist victory, the United States had supported the Kuomintang government with financial and military aid. The fall of the Nationalist government was seen as a significant loss for the United States in the early years of the Cold War, representing the "loss of China" to communism.

This event sparked a strong anti-communist sentiment in the United States and contributed to the rise of McCarthyism in the 1950s, during which there was a heightened fear of communist infiltration and an ensuing period of aggressive investigations and allegations aimed at suspected communists in the US. It also led to U.S. involvement in the Korean War, as the United States became more committed to containing communism in Asia, and later influenced its engagement in the Vietnam War.