Complex sentence: Moreover, Mao and the USSR interpreted Eisenhower's response as an affront to all socialist countries, and the PRC responded with mass rallies demanding that Khrushchev act against the American aggressors.
Split into simpler sentences: Moreover, Mao and the USSR interpreted Eisenhower's response as an affront to the socialist countries of the world. The PRC responded with mass rallies demanding that Khrushchev act against the American aggressors.