Since 228 A.D., every war direction of Shu Han is the Northern Expedition, but every time it is in vain, there is not only a question here, obviously the world is so vast, Shu Han just stared at the north, not to develop in other directions?
To answer this question, it is necessary to understand what kind of existence is written around Shu Han.
First of all, Shu Han was established in the land of Yizhou, in the north is the Yongliang region of Cao Wei, in the east is the ally Soochow, in the south is the current Laos and Burma region, and in the west is the Qinghai-Tibet Plateau.
Since Liu Bei's death, Zhuge Liang chose to continue to be friendly with Eastern Wu in order to be able to deal with Cao Wei wholeheartedly, and even when Sun Quan was called emperor, legally speaking, the other party was also a chaotic minister and thief, but Zhuge Liang still sent people to congratulate Sun Quan to maintain the alliance. In this way, it is impossible to develop eastward.
So if you go south, you must know that one of the preparations that Zhuge Liang made for the Northern Expedition was the Southern Expedition, and he took the first step to pacify Nanzhong. It is precisely because I have been there that I feel that it is difficult to develop in the south. At that time, the land of Nanzhong was already densely forested and full of miasma, so would it be worse further south? You must know that at that time, the further south you go, people called the local people barbarians, and what is "barbarian" is that they have not yet been indoctrinated. Therefore, even if it does go south, then governance and development is a huge problem, and it cannot be done overnight. Zhuge Liang didn't have that much time.
What do you say to the west? To the west is the Qinghai-Tibet Plateau, where some Qiang people lived during that period, or the local indigenous people, coupled with the altitude and altitude, it was not at all possible for the people at that time to solve. This uncharted region is full of too much uncertainty.
So it seems that only the north remains.
The Northern Expedition had many benefits.
First of all, it makes sense legally. Because Shu Han belongs to the continuation of Han Zuo, and Cao Wei belongs to usurping power and seizing power, then it is the obligation of Shu Han to crusade against the other party. Having such a goal will not only help the people to start a war, but also will not make the soldiers understand why they are fighting.
Second, the Northern Expedition was able to obtain enough war horses. The most important type of warfare in ancient times was cavalry, and cavalry required a large number of horses. Because the north was occupied by Cao Wei, Shu Han and Eastern Wu in the south did not have enough war horses**, and Sichuan horses were not suitable for long-distance raids, and Eastern Wu barely obtained horses from Liaodong through sea transportation.
And now in the Northern Expedition, once Liangzhou and Longyou are taken, Shu Han will be able to have a stable war horseIn addition, it can also cut off the connection between Cao Wei ** and the Western Regions.
It is for these two reasons that Shu Han has always been committed to the Northern Expedition, because once the Northern Expedition is successful, the situation of the Three Kingdoms will undergo earth-shaking changes, and the national strength of Shu Han will be rapidly enhanced. As long as it takes several generations of hard work, there is no chance to revive the glory of the Han Dynasty.
It's a pity that Cao Wei stationed elite soldiers and good generals in the land of Yongliang, and every Northern Expedition was a huge test for Shu Han, so he never succeeded.