I think it was Battle of Red Cliffs who made Cao Cao pay too much. After this failure, he no longer has confidence and determination to realize his dream of reunifying the whole country. Why do you say that? Because, Battle of Red Cliffs, let Cao Cao lost a lot of elite, at the same time, the failure of this time, let a lot of people who want to rebel have an opportunity, plus domestic and foreign invasion, middle-aged people he doesn't have that much strength, rather than struggling, it is better to narrow their dreams. Although he no longer wants to rule this country, his ambition has always been there.

Before Battle of Red Cliffs happened, Cao Cao's road to reunifying the whole country was very smooth, with almost no obstacles. The previous battle ended in his victory. As a result, Jingzhou area has become his territory, and will continue to go south to realize the dream of reunification. Unfortunately, something unexpected happened. Zhou Yu took advantage of the east wind to let Cao Cao's 200 thousand army burn. I'm sorry.

In order to keep his inheritance, Cao Cao had to return to the north. After he had another health machine, Liu Bei and Sun Quan also formed an alliance to resist him. At the same time, in his fifties, he realized that his life was approaching and it was difficult to unify the road. He always wants to find some ways to find a way out for his descendants. So he turned his goal to overthrow the Han Dynasty and establish his own rule.

To this end, he launched two wars. The first one defeated Xiliang Army and gained fame. The second defeated Zhang Lu, established his prestige again, and laid the foundation for him to replace Hanwang. Just when he was about to succeed, a battle in Hanzhong made him fall to the bottom again, which prevented him from realizing his dream of becoming a Han by himself in his lifetime, but later his son Cao Pi fulfilled this dream for him.