4. Stereotypes of out-groups. President Truman and his advisors fell victim to the temptation to falsely characterize enemy groups in 1950 with the decision to cross the 38th parallel, a line drawn by the Chinese Communists as a “line in the sand” between North and South Korea. The decision was made despite repeated warnings from Communist China that to do so would be viewed as a declaration of war by the United States on China. How could Truman and his advisors have so seriously misinterpreted the Chinese warnings? The decision was based largely on a false stereotype of the Chinese Communists as being weak and dominated by Russia, who, it was believed, did not want war. The stereotype proved false, and the Korean “police action” became a resounding failure as the Chinese attacked with massive force.