After Lu Xun's defeat of Liu Bei at Yiling in 222 AD, the three kingdoms of Wei Shu and Wu entered a phase of stable confrontation. Of the thirteen states of the Eastern Han Dynasty, the State of Wei monopolized nine prefectures, the State of Wu had three states (Jing, Yang, and Jiao), and the State of Shu had only one Yi Prefecture. It was under these circumstances that Zhuge Liang sent troops to the Northern Plains five times, and the Eastern Wu side did not send troops from Jingzhou to the Northern Expedition except for going around in Hefei (a barrier that Sun Quan could not get around).
The strength of the State of Wu was stronger than that of the State of Shu, and Lu Xun had been in Jingzhou for 20 years, so why didn't he have the Northern Expedition to Cao Wei?
First, Lu Xun's own strategic vision
Throughout the entire Chronicle of the Three Kingdoms, in addition to the emperors, there were only two courtiers listed separately-Zhuge Liang and Lu Xun. Lu Xun followed Sun Quan for more than forty years and commanded the military and government of the State of Wu for more than twenty years. He was a far-sighted, loyal and upright man, and was praised as a "minister of the society". The battles of Jingzhou, Yiling, and Shiting were successively successful, and Lu Xun's military level was beyond doubt.
But Lu Xun's biggest problem is his lack of strategic vision. Not to mention that compared with Zhuge Liang and Sima Yi, between the four governors of Eastern Wu, Lu Xun's strategic vision was also somewhat inferior. Zhou Yu once proposed a plan to divide the whole Yangtze River into two worlds, and Lu Su had a "collapse on the right" as early as 200 AD, that is, Lü Meng, who had a low level of education, also had the vision of a strange plot to attack Jingzhou.
On the other hand, although Lu Xun, the Battle of Yiling and the Battle of Shiting had far-reaching influence, Lu Xun also commanded very beautifully, but they were all passive defenses. Moreover, it is difficult for us to find his strategic opinions on the development of Eastern Wu through the "Biography of Lu Xun", which is rare, and can only show that Lu Xun's enterprising spirit and strategic vision are insufficient (perhaps related to the origin of the Jiangdong Shi clan).
Second, Lu Xun's position in the State of Wu was inferior to that of Zhuge Liang
Although Lu Xun was already in the state of Wu as "above ten thousand people under one person", Lu Xun's right to speak in the State of Wu was simply inferior to Zhuge Liang's right to speak in shu Han. After Liu Bei was entrusted to the orphans on his deathbed, Zhuge Liang was almost a "president of the state", Liu Chan was a person with no opinion, and Zhuge Liang's will represented the will of Shu Han, so Shu Han was able to raise the strength of the whole country five times to the Northern Expedition.
On the other hand, although Lu Xun achieved the high position of "going in and out of the phase", because Lu Xun himself was a representative figure of the Jiangdong Shi clan, Sun Quan also had a strong wariness against him while relying heavily on Lu Xun, so even if Lu Xun intended to go north, I am afraid that Sun Quan would find it difficult to fully support him.
Third, the complex relationship between Sun Quan and Lu Xun
It is no exaggeration to say that it was Lu Xun who defeated Shu Han and Cao Wei successively through the Battle of Yiling and the Battle of Shiting, so that Sun Quan finally ascended to the throne. Sun Quan was also very kind to Lu Xun, and for the sake of Jiashang Lu Xun's merits, he set up a great general on top of the great general, and his status was higher than that of the three dukes. However, the relationship between Sun Quan and Lu Xun is far from being as harmonious as it seems, and in addition to the conflict between Sun Quan and the Jiangdong Shi clan, Lu Xun has several special features:
First, Lu Xun's ancestor Lu Kang, who was lujiang taishou at the time, Yuan Shu sent Sun Ce to attack Lujiang, and Lu Kang, who was nearly 70 years old, died of illness, and in the two years of difficult defense of the city, more than a hundred members of the Lu family clan died, nearly half of them. Although Lu Kang's sons Lu Ji and Sun Luxun later served as officials in Eastern Wu, this hatred buried in his heart could never be completely eliminated.
Second, Lu Xun was Sun Ce's son-in-law. In 204 AD, Sun Quan took the initiative and married the daughter of his brother Sun Ce to Lu Xun, of course, in order to ease the relationship between the Sun family and the Lu family, and to win the Lu family to serve the Sun family sincerely. Sun Quan claimed that the empress dowager did not have high respect for Sun Ce, but posthumously honored him as the Huan King of Changsha. Sun Ce's sons were only given the title of Marquis, and Sun Quan's own sons, no matter how old, were princes, which showed that Sun Quan was deliberately suppressing Sun Ce's line.
The "Chronicle of the Three Kingdoms and the Biography of Lu Xun" contains: Xun was indignant and died, at the age of sixty-three, and the family had no surplus wealth. This record is very clear, saying that Lu Xun was killed by qi, and who killed Lu Xun was angry, naturally sun Quan. In his later years, Sun Quan did not hesitate to force Lu Xun to die, which shows Sun Quan's suspicion and jealousy of Lu Xun, how could such a Lu Xun lead the Northern Expedition?
Fourth, Cao Wei's differential treatment of Wu Shu
After the establishment of the three states of Wei and Shu and Wu, their respective strategies were different, the Wu-Shu alliance jointly dealt with Cao Wei, the Northern Expedition of the Shu Army, intending to encroach on Yongliang; the Northern Expedition of the State of Wu, and Cao Wei's struggle for Huainan; Cao Wei's basic strategy since Cao Cao's defeat in the battle for Hanzhong was to defend the west and attack the east, destroying Wu first and then destroying Shu.
The terrain of Yizhou and Hanzhong was dangerous and easy to defend and difficult to attack, and Cao Wei occupied Huainan, making it easy to gather a large army to attack Wu. After Cao Pi took the throne, he attacked Wu on a large scale, which was the manifestation of this strategy. In 229, under the circumstances of Zhuge Liangxing's Northern Expedition, Cao Rui consulted Sima Yi on "who comes first" Sima Yi clearly replied that the large-scale attack on Wu by land and water was also a strategy of adhering to the western defense and the eastern offensive. In this context, Lu Xun was sometimes busy with defense, and the Northern Expedition could not be discussed.
The Three Kingdoms confronted each other, and the Wu-Shu alliance fought against Cao Wei. The Northern Expedition of the Shu Army, intending to encroach on Yongliang, wu's Northern Expedition, and Cao Wei's struggle for Huainan, seemed to echo each other. However, in fact, the two sides were thousands of miles apart, and the Wu kingdom was really crossed. As cao Wei defended the west and attacked the east, dealing with Shu and Wu with ease, with the passage of time, the disparity in strength between the three countries became more and more serious, and the situation tending to unification was irreversible!
References: Notes on Pei Songzhi in romance of the Three Kingdoms, And Lu Simian in History of the Three Kingdoms