Zhang Handan was also a strange man, originally only a young man of the Qin court, but for some reason, he was promoted by Hu Hai of Qin II, and with a temporary army composed of Prisoners of Lishan and the descendants of prisoners, he defeated Chen Sheng's general Zhou Wen.
Zhou Wen's nearly one million troops, in front of Zhang Handan, actually collapsed in one blow, fled in a hurry, and finally the entire army was destroyed. Subsequently, Zhang Handan even led the Qin army to sweep through the princes of the Six Kingdoms, and even Xiang Liang, the bearer of the Chu State, was killed by Zhang Handan in Dingtao.
If Zhang Handan had not had the heart of a mercenary to stand on his own, even if Xiang Liang's nephew was the later Western Chu overlord Xiang Yu, and could not have won a great victory in the Battle of Julu, Zhang Handan's 200,000 disciples would not have been killed by Xiang Yu overnight in Xin'an.
Zhang Handan was later made the King of Yong by Xiang Yu, and he was also a prince of the party.
However, Zhang Handan, who was established as the Yong King, seemed to have changed from a fierce tiger to a sick cat, and Zhang Handan, who had a vast military talent, did not expect that the King of Han and the great general of the King of Han, Han Xin, would actually play the trick of secretly crossing Chen Cang.
Why did Zhang Handan, who possessed a vast military talent, not expect Han Xin to play the trick of Han Du Chen Cang?
Because Zhang Handan underestimated the determination of Liu Bang, the King of Han, and the Han army to get out of the customs, he could not imagine that Han Xin, the newly established general of the Han King, was a peerless soldier with more military talent than zhang Handan.
Although Zhang Handan possessed a vast military talent, in politics, his rank was far lower than that of Han Xin.
Before the King of Han returned to Guanzhong, Han Xin clearly pointed out that Zhang Handan and the other two Qin kings could not defend the Three Qins at all, and the hearts of the Three Qin people were not in the Three Qins.
When Wang Zhi entered Wuguan, Qiu did no harm, except for qin harsh law, and Qin Min's covenant, the law of the three chapters, Qin min all wanted to get the great king Qin. In the covenant of the princes, the great king was the king of Guanzhong, and the people of Guanzhong knew it. The great king derelicted his duties and entered the Han Dynasty, and the Qin people hated them all. Now that the great king has raised the east, the Three Qins can be passed on to determine the lord. - "History of the Marquis of Huaiyin"
Zhang Handan did not know at all, he did not have to close the hearts of the people, Zhang Handan did not know, the people's hearts and minds to a certain extent determined the outcome of the war. When Liu Bang, the king of Han, entered Shu, Zhang Handan did not issue things such as guilty of his own edict to win the hearts and minds of the people, but blindly pursued and intercepted Liu Bang.
Liu Bang is bound to fight back, can you Zhang Handan block for a while, block a lifetime?
Either you Zhang Handan will pursue Liu Bang and directly overthrow Liu Bang, or you will come up with more ruthless measures to win the hearts and minds of the people than the three chapters of the Law of The Covenant, otherwise, you can only be by Liu Bang.
The fact is also that Zhang Handan divided his troops to guard the key pass, and Liu Bang was indeed blocked for a while, but Liu Bang's desire to return to Guanzhong was too strong, and in the face of Zhang Handan's encirclement and interception, he once again asked Ji Qunchen, and Liu Bang's courtiers were indeed hidden dragons and Crouching Tigers.
Yongjun Sai Chen, Gurudwara, Shangji wants to return, Yan Yan from his Way, Dao Tong. - Chronology of the Princes of Gaozu
A man named Zhao Yan told Liu Bang that there was still a way to Guanzhong, so Liu Bang left Guanzhong from another road and approached Chen Cang.
The reason why there is such a dramatic turn is simply because Liu Bang won the hearts of the people and Zhang Handan was unpopular. If you are unpopular, you will not get enough information, your information will be insufficient, and it will be difficult for you to make the most correct judgment.
References: "History of Gaozu Benji", "History of Xiang Yu Benji", "History of the Marquis of Huaiyin", "Chronology of the Marquis of Gaozu"