In the Three Kingdoms, Monroe beheaded Guan Yu and brought him back to Wu. Why did Sun Quan, the Lord of Wu, kill him?

Sun Quan had to kill Guan Yu because he didn't know what would happen if he didn't kill Guan Yu. In order to avoid future trouble, just kill it. When Lv Meng attacked Jingzhou, Sun Quan had made up his mind to kill Guan Yu.

On the eve of Guan Yu's escape, Sun Quan asked his men to divine and calculate Guan Yu's fate. Guan Yu was about to be beheaded at that time, and Sun Quan said nothing. After Guan Yu's death, Sun Quan also praised his men for their accuracy. Judging from the situation at that time, Sun Quan sent someone to intercept Guan Yu's men and killed Guan Yu as soon as he caught him. I didn't intend to leave him alive at all. Therefore, Sun Quan's determination to kill Guan Yu is very strong, and it is only fast to kill Guan Yu.

But Sun Quan knew in his heart that killing Guan Yu would inevitably be retaliated by Liu Bei. This reason is the same as others' analysis. Guan Yu and Liu Bei, though subjects, are like flesh and blood, and Liu Bei must avenge him. Therefore, Sun Quan took various measures to deal with Liu Bei's revenge.

One is to lead the disaster to Cao Cao. After Sun Quan killed Guan Yu, he gave Guan Yu's head to Cao Cao for good news. He showed the world that he was instructed by Cao Cao to kill Guan Yu. However, Cao Cao broke Sun Quan's attempt with a thick burial of Guan Yu.

Sun Quan's plan is not renewable. He wrote a letter to persuade Cao Cao to proclaim himself emperor, and Cao Cao saw through Sun Quan's attempt at a glance. Cao Cao read the letter and said, Sun Quan is trying to set me on fire. Cao Cao simply ignored Sun Quan's suggestion, which frustrated Sun Quan's attempt.

The second is to launch a diplomatic offensive, unite Cao Wei in the north and block Shu Han in the west. In order to prevent himself from being attacked on both sides, Sun Quan tried his best to get on well with Cao Wei. He made a fool of Cao Wei and paid tribute to him, and gained the neutral position of Cao Wei.

As for him, he asked to write to Liu Bei and advised him not to send troops to attack Wu. Although Liu Bei was not prevented from sending troops, at that time, Sun Quan still grasped the diplomatic initiative.

The third is to advocate the use of young military talents and make good preparations for joining the army. At that time, Liu Bei dared to send troops to attack Wu mainly because he died of illness. According to his understanding of Wu Dong's generals, Liu Bei thought that Wu Dong had no rivals. Sun Quan dared to boldly promote the little-known Lu Xun to command the army, which Liu Bei did not expect.

Lu Xun's military genius is unknown, but it can be seen in the battle that he is a general who can fight against Liu Bei. Wu Dong's strength is not weaker than that of Liu Bei, and he is in a favorable defensive position, which laid the foundation for defeating Liu Bei.

With the above three conditions, Sun Quan was not afraid of Liu Bei's revenge, so he made up his mind to kill Guan Yu. At the same time, if Sun Quan doesn't kill Guan Yu, the next situation may not be beyond his control. If Sun Quan doesn't kill Guan Yu, Guan Yu will definitely return to Liu Bei's hands. In this way, Sun Quan cannot be sure whether Liu Bei will attack Wu Dong if Guan Yu is released.

Because Guan Yu went back alive, but the loss of Jingzhou made Longzhong go bankrupt. With Guan Yu's temper and Liu Bei's strategic intention, they are likely to send troops to recapture Jingzhou while regaining Sun Quan. If so, Guan Yu's military capability is too great a threat to Wu Dong. If Guan Yu's participation leads to Wu Dong's military defeat, Sun Quan will be the one who will let the tiger return to the mountain and bear the consequences. If that happens, it is better to kill Guan Yu, so as not to leave future trouble.

Of course, some people say that Sun Quan killed Guan Yu in retaliation for Guan Yu's unkind words. Although there will be some such reasons, as the king of a country, Sun Quan's main reason is the above considerations, which is also the main reason for killing Guan Yu.