Because of this, the Tang Dynasty declined, and the Song Dynasty learned a lesson and did the opposite. Why is the ending the same?

The concept of governing the country advocated by the Tang Dynasty is "emphasizing the outside but neglecting the inside". In fact, it is easy to understand, that is, the main military forces are placed in the frontier, and all the soldiers guarding the city have only 5 combat effectiveness, which led to the end of the Anshi Rebellion. The strength of the buffer region will definitely affect the power of the central government, which is also the reason for the demise of the prosperous Tang Dynasty.

First of all, learn a lesson and do the opposite.

Li Shimin's most famous sentence is "take copper as a mirror, you can correct yourself;" Taking history as a mirror, we can know the rise and fall; Take people as a mirror and you can know the gains and losses. " Zhao Kuangyin must have seen the reasons for the demise of the Tang Dynasty, so in order not to repeat the same mistakes, the Song Dynasty introduced a policy opposite to that of the Tang Dynasty, that is, "emphasizing the inside and neglecting the outside".

The most direct realization of "attaching importance to the interior and neglecting the exterior" must be to attach importance to the ministers of the DPRK and ignore the frontier soldiers. In Song Dynasty, emperors praised "valuing literature over martial arts", and the status of literati was particularly high and the treatment was particularly good. Even the soldiers fighting at the border are literati. On the contrary, soldiers fighting at the front have no power to dispatch troops.

Second, although it is the opposite, the official career is the same.

For a country to be stable, besides economic development, the most important thing is military strength. It happened that the final demise of the Song Dynasty was due to the fact that there were no ethnic minorities who were brave and good at fighting and suffered from the loss of combat effectiveness. Frontier soldiers are civil servants, and those who really know how to fight private soldiers have no real power and cannot mobilize their troops to attack and defend, which is bound to suffer.

Moreover, in order to prevent the rise of similar buffer zones, generals in border areas have been frequently replaced. This policy has greatly affected the combat effectiveness of soldiers. Every general has a different way of fighting. Frequent replacement of generals needs more time to integrate, and the aspect of "human harmony" has not been paid attention to.