What political system was implemented in the early years of the Western Han Dynasty? What's the problem?

The Western Han Dynasty was a mixture of enfeoffment system and county system!

The Western Han Dynasty was established by inheriting the Qin Dynasty. Most of the political and economic systems in the early years of the Western Han Dynasty were based on the standards of the Qin Dynasty, or drew lessons from the experience of the Qin Dynasty.

In the early years of the Western Han Dynasty, it was concluded that the Qin Dynasty implemented a thorough county system, so when the central government was in danger, it could not get local support and assistance. In Liu Bang's view, if the enfeoffment system is implemented, then the state controls some local forces in China, and the emperor controls the central government and counties. If there is a local rebellion, even if the central government is unable to suppress it, the enfeoffment country can provide support and protection. After all, most governors are relatives! Especially after Liu Bang cut off almost all queens with different surnames, all the heads of the kingdom came from the same family and were related by blood. In the eyes of Liu Bang and other founding fathers of the Western Han Dynasty, consanguinity is obviously quite reliable.

This is similar to the situation that Jin re-implemented the enfeoffment system after the Three Kingdoms. In the Three Kingdoms, although Wei sealed many governors, the king did not. As a result, the Cao family could not compete after Sima came to power, and the feudal system was reused after the establishment of Jin.