From this point, it can be seen that Emperor Wen of Wei Cao Pi knew more about military affairs than Emperor Liu Bei of Zhaolie of the Han Dynasty, but it was not only in military affairs that caused Liu Bei's fiasco.
During the Three Kingdoms period, Guan Yu, who guarded Jingzhou and was Liu Bei's sworn brother, fell into the hands of Sun Quan and Lü Meng of Eastern Wu, and finally lost Maicheng and was killed.
So in order to avenge Guan Yu, Liu Bei did not listen to the persuasion of Zhuge Liang and others and personally led troops to crusade against Eastern Wu, resulting in the loss of nearly 100,000 elite troops of Shu Han, and he also died in the White Emperor City soon after.
Of course, there is a lot of analysis of this battle itself in history, but the fundamental point lies in Liu Bei's mistake in the strategic decision to attack Eastern Wu.
Sun Tzu's Art of War says: The Lord should not raise an army in anger, nor does it mean that a king should not start a war because of his own anger.
Guan Yu was killed and Jingzhou was lost, which was undoubtedly a huge fiasco and loss for the Shu Han regime. Liu Bei's mood of wanting to take revenge and regain the lost territory is understandable, but the reality at that time was that it was impossible to recapture Jingzhou militarily, so he could only send troops to avenge his brother, and such a reason for sending troops was obviously not very good at mobilizing everyone's enthusiasm.
Of course, it is impossible for the three kingdoms of Wei, Shu and Wu not to carry out military conquest against each other, but the strategic decisions made on the premise of personal emotional loss of control and anger will lead to blind movements under various subjective and objective conditions and bring huge losses.