At this time, Cao Cao was very shocked. Although Coss, a "defense expert", was in Tongguan, he was not at ease, so he led the army to support Tongguan and crusade against Ma Chao. Then, what are the multiple uses of Tongguan, and Cao Cao did not hesitate to pour out the power of the whole country to crusade against Ma Chao? Personally, I think Tongguan is the key to the Three Qin Dynasties, the gateway to Chang 'an, Tongguan is here, Chang 'an, Tongguan fell, and Ma Chao is also a master of Xiliang, which deserves Cao Cao's personal conquest.
The Importance of Tongguan Geographical Location
First, Tongguan is the key to Sanqin.
Tongguan, located at the Yellow River Ferry, is located at the crossroads of Shanxi, Shaanxi and Henan provinces. If you occupy Tongguan, you can guard the intersection from Chang 'an to Luoyang Post Road. It is the key point for Guandong to enter and leave the Three Qin Dynasties, and has always been a battleground for military strategists, replacing the position of Hanguguan in the pre-Qin period. Tongguan is known as "the first risk in Guinea", "the throat of four towns" and "a hundred puns".
Second, Tongguan is easy to defend but difficult to attack.
Tongguan is located in the north of Tongguan County, Weinan City, Shaanxi Province, with the Yellow River in the north and the mountainside in the south. This pass was set at the end of the Eastern Han Dynasty, about the first year of Jian 'an in the Eastern Han Dynasty (AD 196). Tongguan is the east gate of Guanzhong. Even Emperor Qianlong of the Qing Dynasty traveled here, deeply impressed by the rigor of Tongguan, and left the "first pass" gilded imperial book outside the tower.
Why did Cao Cao lead an army to conquer Ma Chao?
First, the west cool Ma Chao fighters are brave and good at fighting, and Coss can't stop them.
The folkways in Xiliang are tough, especially the cavalry, who come and go without a trace, and travel to the West. In those days, Xiliang Dong Zhuo led an army into Luoyang, "holding the emperor to make the princes". At that time, the governors of the 18 th Route of Kanto reluctantly drove Dong Zhuo away, and they did not completely eliminate Dong Zhuo's soldiers in the west. Now it's not just a warlord Ma Chao who rebelled, but ten forces headed by Ma Chao and Han Sui, which are huge. Ma Chao ranked fifth in Romance of the Three Kingdoms, one higher than Zhang Fei, a Yan man. Coss is an old general, but compared with Ma Chao, there is still a big gap.
Cao Cao is still afraid of Ma Chao. After Ma Chao's rebellion, he did not kill Marten, Matthew, Ma Tie and others in Beijing for the first time. It can be seen that Cao Cao dared not do anything, wanted to threaten Ma Chao, and even made a deal with Ma Chao. As mentioned in the Romance, Ma Teng, Matthew, Ma Tie and others were killed by Cao Cao, and Ma Chao only raised the banner of rebellion, which has a certain gap with the official history. Marten and others were killed because in the second year, Ma Chao made a comeback in Liangzhou and conquered the counties in Gansu before being killed.
So Cao Cao was afraid of Ma Chao. To be on the safe side, regardless of his age, he led an army to war and personally arranged troops to nip the allied forces of Ma Chao and Han Sui in the bud. If the rest of the people rebel, Cao Cao doesn't have to lead troops to conquer himself, but send a general to pacify him.
Secondly, Cao Cao led the army to conquer Ma Chao, in order to ensure that Tongguan was foolproof.
Tongguan is the gateway of Guanzhong Plain, and it is of great significance to hold Tongguan. If Tongguan falls, Cao Cao will lose the Guanzhong Plain and suffer heavy losses. If we want to keep the Guanzhong Plain and Xijing Chang 'an, we must first ensure that Tongguan is foolproof. Cao Cao originally wanted to crusade against Zhang Lu who had not surrendered by way of Hanzhong. As a result, Ma Chao, Han Sui and other warlords were strongly dissatisfied and war broke out. Cao Cao was worried about Tongguan, fearing that Cao Renbing was few and could not stop Ma Chao's army.
Cao Cao's worry is justified. In the romance, Coss was guarding Tongguan for less than ten days before he fell. Therefore, Cao Cao had to raise food and grass and personally lead troops to conquer Ma Chao. At first, Ma Chao killed him, cut his beard and abandoned his robe. Finally, Cao Cao adopted Jia Xu's double spy and succeeded in alienating Ma Chao and Han Sui. Only by defeating Ma Chao can we succeed and keep Tongguan.
Summary: Tongguan is the gateway of Guanzhong Plain, where Tongguan is in, Guanzhong is safe, Tongguan is lost and Guanzhong is in danger. Therefore, in order to keep the fertile Guanzhong Plain, Cao Cao had to personally lead an army to crusade against Ma Chao. The two sides held an earth-shattering Armageddon in Tongguan, which ended in Cao Cao's complete victory. Cao Cao saw the importance of Tongguan, which is the key to Sanqin. If he wants to keep the Guanzhong Plain, he must keep Tongguan. So Cao Cao personally led the troops to conquer, supported Tongguan with lightning speed, divided and disintegrated Han Sui, Ma Chao and other ten allied forces, and pacified Xiliang.