After Cao Cao executed Lu Bu, why did he turn his head and regret it? As everyone knows, he fell into the trap of others. I believe that whenever Lu Bu is mentioned, in addition to knowing that this person's martial arts are strong, he is the most capricious person and has no benevolence, righteousness and morality.
So this is also the problem that made Cao Cao the most headache later, when he captured Lu Bu alive, he wanted to appoint Lu Bu in his heart, but also worried that he would be stabbed by Lu Bu again one day. In fact, Cao Cao naturally wanted to be more inclined and chose to give Lu Bu another chance, but he asked Liu Bei what he thought at that time, intentionally or unintentionally.
And Liu Bei seems to be very calm, but in fact, he is afraid that Cao Cao will really accept Lu Bu, because in this way, Liu Bei can only have one more strong opponent. With the blessing of Lu Bu, maybe this world will really become Cao Cao's, so Liu Bei's thoughts can't be too obvious, so he took Ding Yuan and Dong Zhuo as a reference
That is, to see if Cao Cao wants to be Lu Bu's third father-in-law? It was precisely because of this sentence that the suspicious Cao Cao made up his mind to execute Lu Bu. But afterwards, Cao Cao must be an understanding person, it is impossible for him not to know that this is Liu Bei's intention, although Cao Cao never mentioned it on the surface, but he really never regretted it in his heart?
After all, it was a unique peerless general in the entire Three Kingdoms, how could he be reluctant to give up on Cao Cao, who had always loved talents? If it weren't for Liu Bei's words, I believe that Cao Cao would still have a high probability that he would let Lu Bu help him sweep the Three Kingdoms.