The Battle of Chibi led to an alliance between Liu Bei and Sun Quan, a loose political alliance that existed because of the existence of Cao Cao, the common enemy of both sides, but there was no eternal ally and no eternal enemy, because of the change of the situation at that time, Cao Cao and Sun Quan's former opponents were secretly united, Sun Quan chose to betray the nominal alliance with Liu Bei, chose to secretly attack Jingzhou, and went all the way to the end, and also killed Liu Bei's brother Guan Yu and dedicated the first rank to Cao Cao.
So the question is, why did Sun Quan do this? What is the benefit of doing this to Sun Quan?
The core area of Sun Quan's power is the six counties of Jiangdong, since the era of Sun Ce, the Jiangdong Group has been constantly developing externally, from a strategic point of view, the development direction of the Jiangdong Group is only two directions, one is to advance north into the Central Plains, when Sun Ce wanted to go north to capture Xuchang, and died at the hands of assassins.
Sun quan
The other direction is to seize Jingzhou with the west, Lu Su once said to Sun Quan in the "bed" that Cao Cao is temporarily invincible, and we must now take the opportunity to destroy Huang Zu, attack Liu Biao, all south of the Yangtze River, and finally establish the imperial title, and compete with Cao Cao in the north for the world, which is the Longzhong confrontation strategy of Eastern Wu in history.
"Romance of the Three Kingdoms" Lu Su Biography: Eliminate Huang Zu, enter Liu Biao, even the Yangtze River pole, according to it, and then build the emperor to try to the world, this high emperor's cause is also.
Few people have noticed one of the sentences that Lu Su said, that is, "compete for the pole of the Yangtze River, according to it", the meaning of this sentence is: across all the territory south of the Yangtze River and try to occupy, note that Lu Su said that the entire South of the Yangtze River, more than half of the land in Jingzhou is south of the Yangtze River, and the south of the Yangtze River also includes the upper reaches of the Yizhou area.
Lu Su's strategy for Sun Quan was to take all the land south of the Yangtze River
Therefore, before the Battle of Chibi, Sun Quan marched against Huang Zu in Jiangxia and finally succeeded in attacking Huang Zu, just when Sun Quan was preparing to continue to expand the results of the battle, Cao Cao went south, and the situation in the whole world changed instantly, and the strategy of sun quan's group was expanding to the west (in the direction of Jingzhou) changed, and became a strategy to resist Cao Cao from the north, in order to unite other forces as much as possible, Sun Quan allied with Liu Bei at the suggestion of Lu Su.
The Battle of Chibi and the Battle of Nan Commandery followed, with Sun Quan's combined forces with Liu Bei defeating Cao Cao, a coalition led by Zhou Yu defeating Cao Ren and occupying Nan Commandery in Jingzhou, while Liu Bei seized the opportunity to capture the four counties of Jingnan (Wuling County, Changsha County, Lingling County, and Guiyang County).
After that, Zhou Yu proposed the strategy of taking advantage of the opportunity to capture Yizhou, noting that this was the strategy proposed by Lu Su to be all south of the Yangtze River, but it was only proposed by Zhou Yu, and the important thing was that Sun Quan also agreed to Zhou Yu's request, but Zhou Yu suddenly died of an acute illness on the way back to the army, which led to the inability to implement this major strategy of the Jiangdong clique.
Zhou Yu also proposed to capture Yizhou south of the Yangtze River
So the strategy of the Jiangdong clique changed again, Sun Quan, at the suggestion of Lu Su, lent Nan Commandery to Liu Bei, and also hoped to form a coalition army with Liu Bei to capture Yizhou, but Liu Bei's strategy was to occupy Jingzhou and Yizhou, and what Liu Bei wanted to do was also to seize Yizhou, which was in conflict with Sun Quan's strategy, so Liu Bei tried his best to prevent Sun Quan from meddling in Yizhou, and at the same time, because Liu Bei borrowed Nan County, and Nan County separated Yizhou from Jiangdong, Sun Quan could not skip Liu Bei and directly attack Yizhou.
In 211, Liu Bei was invited by Liu Zhang to enter Yizhou, and through more than two years of war, Liu Bei captured Yizhou, so Liu Bei occupied the five counties of Yizhou and Jingzhou (Nan County plus Jingnan Four Counties), Sun Quan asked Liu Bei for three counties of Changsha County, Lingling County, and Guiyang County, but Liu Bei disagreed, and a large-scale confrontation broke out between the two sides, and finally under cao Cao's pressure, Liu Bei ceded Changsha County and Guiyang County to Sun Quan, and the two sides shook hands and made peace.
The strategies of the Liu Bei clique and the Sun Quan clique are completely in conflict
Going back to compare the strategy of the Sun Quan Group and the Liu Bei Group, the strategy of the Sun Quan Group is to occupy all the south of the Yangtze River, and the strategy of the Liu Bei Group is to occupy Jingzhou and Yizhou, and the strategy between the two sides is completely in conflict, because Jingzhou and Yizhou originally belong to the south of the Yangtze River, and they also guard all the strategic passages in the middle and upper reaches of the Yangtze River.
Therefore, the Sun Quan group and the Liu Bei group are basically two groups with conflicting interests, they have both the basis for cooperation against Cao Cao, and the common conflict of interest, from the perspective of the alliance between the two sides, the two sides are only in the honeymoon period for a period of time before and after the Battle of Chibi, and most of the other time is a discord between the face and the heart, the so-called Sun Liu alliance is just a nominal alliance, in fact, both sides are mutually defensive.
For example, during the period when Guan Yu was guarding Jingzhou, a lot of beacon towers were set up on the edge of the Yangtze River to prevent the raids in Jiangdong, and when Lü Meng sneaked into Jingzhou, he still disguised his soldiers as merchants to sneak attack these beacon towers to successfully seize Jingzhou, which was the defense, although Lü Meng and Lu Xun repeatedly fooled Guan Yu, but Guan Yu did not remove these beacon towers, he was still guarding against Jiangdong, which shows the depth of the contradictions between the two sides.
Guan Yu had been guarding Against Jiangdong
Therefore, the first reason why Sun Quan was desperate to sneak into Jingzhou was that the strategy of the Jiangdong Clique was like this. From 200 AD, when Sun Quan had just become the lord of Jiangdong, Lu Su proposed that Sun Quan have all the yangtze river, which was 7 years earlier than Zhuge Liang's Longzhong strategy, and Sun Quan had been implementing this strategy south of the Yangtze River throughout the entire ruling process.
Although Lu Su offered to unite with Liu Bei to defend against Cao Cao after the Battle of Chibi, after Lu Su's death, there was a high call for Jingzhou within the Jiangdong clique, and Sun Quan began to deploy the strategy of capturing Jingzhou after Lu Su's death, and in 217 he sent an emissary Xu Xiang to negotiate peace with Cao Cao, and the two sides concluded a political marriage.
In the spring of the twenty-second year of the Three Kingdoms Chronicle of Wu, the biography of Wu :( Jian'an), the governor of the imperial order Xu Shuyi cao gong asked to surrender, and the communiqué made him good and vowed to remarry.
Sun Quan and Cao Cao's political reconciliation should have been carried out in secret, judging from the later situation, Liu Bei's clique did not know about this incident, otherwise he would have reminded Guan Yu long ago that the only purpose of Sun Quan and Cao Cao's request to surrender and conclude a political marriage was to prepare for a sneak attack on Jingzhou, and then Sun Quan had been looking for an opportunity, but Guan Yu guarded Jingzhou, so Sun Quan did not have much chance, so Sun Quan waited, and finally let Sun Quan wait for the perfect opportunity, which was the outbreak of the Battle of Xiangfan.
Sun Quan did not hesitate to submit to Cao Cao in order to seize Jingzhou
Judging from the strategic planning of Sun Quan Group, it was natural that he would sneak attack Jingzhou, and sooner or later something would happen, from a historical point of view, it felt very sudden, but from the perspective of Sun Quan's strategy, it was not sudden, but it had been planned.
The second reason why Sun Quan's clique wanted to sneak into Jingzhou even if it betrayed its alliance was to enhance the strategic security of the Jiangdong regime.
Where did Cao Cao's campaign against Chibi come from? Coming from Jingzhou, after Cao Cao occupied Jingzhou, he set out from Jiangling City (江陵城, in present-day Jingzhou, Hubei Province), led a large army of land and water along the Yangtze River, and then met Sun Liu's combined army at Chibi, this time Cao Cao was defeated, and Sun Quan temporarily lifted the threat, but it did not mean that Sun Quan was once and for all.
The most basic means of sun quan regime to guard against the cao wei regime in the north is to rely on the natural dangers of the Yangtze River and use a powerful water army to block Cao Wei, after all, in terms of strength comparison, the Sun Quan group is not half of the Cao Wei group, but on the water army, the Sun Quan group can kill the Cao Wei group in a second, do not underestimate the Yangtze River, this is a proper natural danger in ancient times, Wei Wen Emperor Cao Pi once said: The heavens created the Yangtze River is to divide China into north and south.
The Yangtze River is a natural risk of Jiangdong Group
However, Sun Quan's Yangtze River natural danger is not without weaknesses, its weakness is in the middle and upper reaches, because Sun Quan does not control the middle and upper reaches, so he has always been worried that someone will use the middle and lower reaches of the Yangtze River to attack the lower reaches of the Yangtze River, once there are hostile forces controlling the middle and upper reaches of the Yangtze River, they can train sailors and build warships in the middle and upper reaches of the Yangtze River, so that the power of the Yangtze River natural danger will be reduced by half.
Jingzhou and Yizhou, which occupy the middle and upper reaches of the Yangtze River, can also cross the Yangtze River from Jingzhou to Changde south of the Yangtze River, then cross Dongting Lake to Changsha, and then from Changsha to the east to bypass the Yangtze River from land to attack the hinterland of Eastern Wu, which is a very big risk for Sun Quan, when Cao Cao did not launch the Battle of Chibi, heeded Jia Xu's advice, rested in Jingzhou for several years, and then divided into several roads, attacking Sun Quan by land and water, Sun Quan will undoubtedly be defeated.
During the Battle of Chibi, Cao Cao attacked from Jingzhou
Therefore, if Sun Quan wants to plug this loophole, he must base himself entirely on the Yangtze River, and if he wants to take full control of the Yangtze River, he must take action against Liu Bei and sneak into Jingzhou, because Liu Bei has no possibility of ceding Nan County to Sun Quan, and Liu Bei's strategy is also to go north from Nan County to the North to the Central Plains, without Nan County, Liu Bei cannot go north from Jingzhou.
Sun Quan's sneak attack on Jingzhou was correct from a tactical point of view, which expanded the strategic security of the Jiangdong clique, but from the perspective of the entire tianxia strategy, it was wrong, because such an act seriously dealt a blow to Liu Bei's forces, causing Liu Bei's forces to stagnate from then on, Liu Bei's clique was originally the weakest, after this blow, the possibility of the success of the Northern Expedition was lost, there was no Shu Han regime Northern Expedition to contain Cao Wei, Cao Wei put all the strategic attack on Sun Quan, sun Quan endured more than 70% of the attack force of the Cao Wei clique.
Although during zhuge Liang's 11 years in power, Shu Han had the ability to carry out the Northern Expedition, but that was only a return to the light, completely relying on Zhuge Liang's strong ability to support it, after Zhuge Liang's death, the Shu Han clique has been declining, until the demise, Shu Han perished, Eastern Wu naturally could not live alone, which formed three families into one.
Sun Quan's sneak attack on Jingzhou led to the unification of the Three Kingdoms
In a sense, Sun Quan's successful sneak attack on Jingzhou led to the unification of the Three Kingdoms. Without Sun Quan sneaking into Jingzhou, Guan Yu would not have died, even if he could not take Xiangfan, he could safely return to Jingzhou, and then accumulate strength for the Northern Expedition, so that cao Wei's national strength was constantly consumed, Eastern Wu could share most of the strategic pressure, and there was no later defeat of Liu Bei in the Battle of Yiling, so that the three kingdoms really could not be unified in the short term, this was Sun Quan's strategic short-sighted behavior, he forgot the truth of the cold lips, once Shu Han perished, Eastern Wu was not far from extinction, after all, the gap in national strength was here.