Answer:
Because they violated basic human rights.
Explanation:
Kublai Khan was one of China's greatest emperors. He achieved the unification of that country by annihilating the national Song empire (1279). Contrary to former custom, he treated the deposed imperial family well and forbade his generals from resorting to indiscriminate slaughter.
Answer
What history book? Or what program?
People began to seriously question communism