Amendments
Example: the bill of rights
The answer to your question is: The emperors had lacked the leadership skills to rule the dynasty and the officials were also corrupt. Because of the corruption and mismanagement of the dynasty, a certain group led by Zhu Yuangzhang went against the dynasty and caused the fall.
The answer would be true. The United States put forth this policy because after WWll we did not want anything else to happen like it did in Nazi Germany so in essence we became a policing country to try and stop any evils in the world. In this case the ultimate evil was Communism.
