Reason:

1, learn the lesson of Qin's demise.

2. Rulers know from practice that governing a country must be both civil and military.

Years of war, especially serious economic damage, it is difficult to develop without a period of recovery.

Emperor Wenjing adopted a relaxation policy, which strengthened his national strength and made the society relatively stable. The history of "ruling the world" in the feudal era is called the rule of cultural scene.

It laid a strong material foundation for Emperor Wu of Han Dynasty to drive Xiongnu to the north.