How to strengthen border defense facilities?

In ancient China, nomadic troops with cavalry as the main body rode well, came and went freely, and were erratic and maneuverable, while the troops with infantry as the main body in the Central Plains Dynasty were dwarfed and often faced a dilemma: if too few troops were deployed in the border areas, they would be vulnerable to attack; If troops are mobilized from the mainland to conquer, the other side will act quickly, so the Central Plains army will often be exhausted. Therefore, in view of the different characteristics of people's lives and armed forces in border areas and inland areas, according to the principle of focusing on fortification and defense, starting from the needs of the overall situation of strategy and campaign, it is undoubtedly an effective way to concentrate certain manpower, material resources and financial resources on national defense engineering construction in border areas according to local conditions, make up for the shortage of national defense forces, improve the national defense situation, and then grasp the initiative in war.

Build a city and a town, and stick to the main points.

In the era of cold weapons, attacking high cities and deep pools is undoubtedly a difficult form of combat, so military strategists often do not advocate attacking cities. For example, Sun Tzu's Art of War listed siege as the last resort. Therefore, it has become a very important method of defensive operations to use natural disasters or various defensive projects artificially constructed to preserve and improve their own combat effectiveness and improve operational conditions, and "blocking the city because of danger" has always been a very important defensive thought in China's military history.

Fortification defense appeared in the Xia Dynasty in the early history of China. During the Western Zhou Dynasty, there were records of building castles in the border areas, such as the poem "Xiao Yachu Che", which said that "Wang Ming went south and went to Fangcheng", and the "Fangcheng" in the poem was a castle built by Zhou Xuanwang to defend the nomadic people in the north. Since then, with the frequent wars, it has been quite common to build military strongholds along the border during the Spring and Autumn Period. In order to meet the needs of the war, while the linear fortified positions appeared, some vassal States, such as Qi and Chu, began to gradually connect these border castles with city walls, forming the "Great Wall". In the Warring States period, great powers such as Qin, Wei, Han, Zhao and Yan successively built the Great Wall for common defense. At the same time, in order to resist the harassment and plunder of nomadic people such as Donghu and Xiongnu, the northern vassal States also built linear fortifications connected with border towns, thus forming a defense system called "Great Wall" by later generations.

The mature idea of building a city in the pre-Qin period was inherited by later generations. After Qin Shihuang unified the whole country, in addition to using a lot of manpower and material resources to build the Great Wall of Wan Li from Lintao to Liaodong, he also set up counties and counties in the northern border areas and established border towns as the outpost foundation for the Central Plains dynasty to govern the border areas, thus erecting an artificial national defense barrier in the northern part of the Central Plains. Since then, building a city defense in the border area has always been regarded as a means for the Central Plains Dynasty to prevent the northern nomads from going south. For example, in his letter to Emperor Wen of the Han Dynasty, Chao Cuo thought that the best way to "guard the border for sealing" was to "clear the way into Sichuan and set up a city to close the danger" along the border, and "dig deep into the high city, have stones (that is, stone throwers), and then" migrate people to the real border "to enrich the frontier.

According to this idea, all previous dynasties attached great importance to the construction of national defense projects in border areas, taking perfect defense facilities as a strategic stronghold to curb the rapid advancement of nomadic cavalry. For example, in the Han Dynasty, the central government took the construction of urban towns as a strategy to strengthen the border, and built many towns of different sizes in the southeast and northwest frontiers according to military needs. These cities are smaller than ordinary counties and counties. Some were built on the original settlements, some were built on the newly opened settlements after the "immigration border", and some were built on the wilderness for temporary military purposes. Due to the different importance of strategic and tactical positions, the number of people and troops in the city are also different, and the scope of the city is also different. Geographically, these towns are all in danger, to the point, built on the traffic arteries that are easy to defend but difficult to attack or must be adhered to. They are not only the political center of the central government's administrative management of the border areas, but also the frontier strongholds and military towns that control and defend the border areas militarily.

The Tang Dynasty set up hundreds of military towns in important areas of the country, most of which were located in frontier areas. Only the Anxi viceroy in the northwest frontier has set up four military towns, namely, Qiuci, Khotan, Shule and Broken Leaf, and set up a whole set of military institutions, such as troops, towns and guards, in various important passages and areas under the jurisdiction of the Anxi viceroy and the Beiting viceroy. These military institutions generally have towns in their residences. In the Ming dynasty, the system of health centers was implemented, and health centers were set up on land and sea all over the country and in secondary places. According to records, in the Ming Dynasty, 18 military towns were set up at the junction of Xinjiang, Tibet and Gansu, Qinghai, Sichuan, Tibet and Xinjiang. The establishment of these military towns has played an important role in offsetting the advantages of nomadic cavalry's rapid mobility and effectively ensuring border security. The Qing Dynasty also attached great importance to the fortification of border areas, such as setting up a 14 big city in three northeastern provinces, stationing 22,000 troops, training and arresting13,000 brave soldiers, temporarily garrisoning and guarding the border, and being under the jurisdiction of General Shengjing; There are 8 big cities in Jilin, with a garrison of 1.5 million, which belongs to General Ningguta (now Old Street, Hailin County, Heilongjiang Province); There are130,000 soldiers in a big city in Heilongjiang, under the jurisdiction of general Heilongjiang, and stationed in Aihui City. In Mongolia, Wusitai City (now Zabu Harant, Outer Mongolia) and Kebuduo City were built, and docks and platforms were built along the way from Chahar to Balikun, and elite troops were selected to station. In addition, around Ili City, where General Ili, the highest administrative military chief stationed in Xinjiang, is located, the Qing government has built nine castles successively, forming a situation where stars gather, and the garrison accounts for 1/3 of the total force in Xinjiang.

Since the Han Dynasty, the territory of China has been steadily stabilized for many reasons, but the general plan of "focusing on the river and setting up the city" and sticking to important positions undoubtedly played an important role.