One reason is that China is geographically closer to North Korea than the United States is. Also, both China and North Korea are communist countries, and China fought with North Korea during the Korean War, while the United States fought against North Korea.
The Inca Empire, or Inka Empire (Quechua: Tawantinsuyu), was the largest empire in pre-Columbian America. The administrative, political and military center of the empire was located in Cusco in modern-day Peru. The Inca civilization arose from the highlands of Peru sometime in the early 13th century.
Answer: The stong nationalism of the Serbians.
Explanation: The Serbians were against plans of Austria-Hungary to colonize their land.