The value of this place in the northeast to our country is presumably very clear to everyone, whether it is Russia or Japan, they have coveted it for a long time in modern times. However, I don't know if you have found it, there are many ancient dynasties such as the Qin Dynasty today, but they chose to take the lead in conquering Jiangnan, why did the government do this? Doesn't he know the value of the Northeast?
In fact, as everyone knows, there are many political powers that have emerged in this part of the northeast of the past dynasties, and the threat to the Central Plains Dynasty is also quite large. In addition to the Khitan who established the Liao state and the Jurchen who established the Jin state, in the later period, there were the sons of the Eight Banners of Manchuria who roared down to establish the last feudal dynasty of our country, the Qing Dynasty. Therefore, in this sense, as a powerful Central Plains Dynasty, it should first eliminate the huge threat from the northeast.
However, everyone also saw that even in the Extremely Underdeveloped Qin Dynasty, what the emperor thought of in terms of expanding the territory after cutting off the Six Kingdoms and completing the unification was first of all to develop in the southeast direction. In fact, judging from the conditions of the Qin Dynasty at that time, whether or not it was possible to take the lands of South Vietnam, it was very difficult to achieve effective rule. Therefore, it can be said that there is a reason why Yingzheng did not do so.
The first is the military aspect. Although the performance of the Song Dynasty was very nestled, after the Qin, there were still powerful Central Plains dynasties like Han, Tang and Ming. But almost none of them will pay attention to the northeast, even Li Shimin, who is keen to expand the territory, is interested in the Goryeo countries, and there is no action in the direction further north. Because for them, there's no value there.
The second is the economic aspect. Some people may say that there is a large number of people there, which can be solved by immigration. But in fact, in ancient times, this was very difficult, unless it was due to strategic needs such as stationing on the border. In addition, at that time, whether it was agriculture or transportation, and other aspects of technology, it was difficult to meet the ambitions and unlimited claims of the emperors of successive dynasties for land. To use a big vernacular, it is too uneconomical to occupy there, and it is not enough to make ends meet, and only a fool will allow it.
Again, from the perspective of administrative settings. Although the Qin Dynasty introduced the county system, it was more symbolic, and the real effect was only reflected in later generations. In fact, at the beginning of the founding of the People's Republic of China, in line with the principle of denying all the Qin Dynasty, he still engaged in a period of time to divide the seals - do not think that the system that we are effective now can play its due effect in ancient times.
It is precisely because the conditions are not available that the powerful dynasties of ancient times can only set up methods such as the capital protectorate for remote areas to maintain a formal occupation. Even in the Qing Dynasty, when they exiled prisoners, they all took Ninguta as a natural choice, which shows that in their minds, it is very difficult to live there! In contrast, the wealth of Jiangnan is even more mouth-watering.