In the fifth year of Jianxing (227), Zhuge Liang led the army to the northern expedition of Hanzhong and stationed in Shima and Yangping in Mianbei, where he fought a "war example". Zhuge Liang called his generals to discuss the strategy of the Northern Expedition. Wei Yan said, "I heard about Xia Houmao, and my husband was too timid to plan. Today, 5,000 elite soldiers will be delayed and 5,000 grain will be lost. We go straight from the praise, follow the Qinling Mountains to the east, and go north at noon, but we can reach Chang 'an in ten days. When he hears that Yan Yan is coming, he will abandon the city and run away. In Chang 'an, there is only suggestion Zhao Jing. Hengmen Dige and Sanren Valley are both delicious foods. Compared with the east, it is still 20 days, and it is enough for the public to come from the oblique valley. In this way, the west of Xianyang can be decided in one fell swoop. " Then "it must be in Tongguan, such as the story of Han Xin, which makes it clear but not possible." "Procrastination is often called light, sighing and hating yourself is endless." The contradiction between Wei Yan and Zhuge Liang arose from this, and Wei Yan's "meridian valley plan" became the earliest blitzkrieg theory in the history of war, and also became the focus of debate throughout the ages. Then let's see if Wei Yan's plan is feasible. By the Northern Expedition in 227, Wei Yan had been guarding Hanzhong for eight years. He knew the geography near Hanzhong and the defense around Wei like the back of his hand, so Wei Yan gave Zhuge Liang his plan for many years before sending troops. It is suggested that we should follow the example of Han Xin and Huaiyin Hou in the Western Han Dynasty and part ways with Zhuge Liang. He led ten thousand troops from the Meridian Valley, and he could meet Tongguan in Chang 'an in ten days, so as to refuse the reinforcements from Wanluo. Why did Wei Yan say it would take ten days to arrive? The Meridian Road was opened in the Western Han Dynasty, and the people in Hanzhong have been walking for a hundred years. It is obvious how long it will take to get to Chang 'an. However, attacking Chang 'an is a major event. In eight years, Wei sent a scout, saying that the meridian was 420 kilometers long, and it was not an exaggeration for the elite soldiers to travel 42 kilometers a day. Some people say that Cao Zhen didn't go out for more than 30 days from the Meridian Road (after the main biography, Cao Zhen walked in the oblique valley), but it rained for as many days as Cao Zhen walked, and it was still raining heavily. It is precisely because of this rare heavy rain that Wei San's road felling in Sichuan fell through. So it won't rain when Wei Yan walks through the meridian valley? Cao Zhen walked in the meridian valley in July, which was really rainy season, while Zhuge Liang's first northern expedition was in spring, which was rainy season. Even if it rained, it was light rain. Look at Zhuge Liang's five northern expeditions, except that the second one was launched suddenly. The other four expeditions were all in spring. Why? Because it is rainy in summer and autumn and snowy in winter in a year, it is not suitable for mountain fighting, but only in spring. "At first, Wei Yi-Zhao Hanlie was dead and a few years old, slightly unprepared." Wu attacked Wei Jiangxia and Xiangyang, Wei was in Wanluo, and Sima Yi attacked. The defense near Chang 'an is empty. Chang 'an Shoujiang is Xia Houmao, who is Xia Houmao? "qinghe princess, squire's daughter, is not very friendly with Emperor Wen. She acceded to the throne, thinking that General Anxi was in charge of Guanzhong, the town of Chang 'an, and made Cheng Yuan the land. "Xia Houmao is the neutron of Xia Houdun." Without military strategy, it is easy to cure life. ""When Xun was in the west, there were many concubines, and the princess was at odds with Xun. " Such a fly in the ointment for Liang's children, the flying eagle and the wild dog, can make Chang 'an all over the city, all because they are relatives of Cao Shi, married qinghe princess, Cao Cao's daughter, and are closely related to Cao Pi. After xelloss succeeded to the throne, Xia Houmao was named General Anxi, the town of Chang 'an. Therefore, Wei Yan said that he was "timid and had no plan". "When he heard that Yan Yan was coming, he would abandon the city and flee. "Xia Houmao compared with Wei, just as Ma Su compared with Wargo, so did the defenders. Can this city persist? At that time, there were about 5,000 soldiers in Chang 'an, which was similar to Wei Yan's troops. But Wei Yan is a good soldier. Wei Yan is a battle-hardened general. It's not a big problem to win Chang 'an. Facts have proved that as soon as Zhuge Liang came out of Qishan, Wei Mingdi was replaced by Chang 'an Shoujiang. However, the armies of Wei and Shu are very different. It is easy to capture Chang 'an, but difficult to hold it. Chang 'an is located in Guanzhong Plain, suitable for cavalry fighting, and Shu soldiers are good at mountain fighting. Under the impact of cavalry, the Shu soldiers were definitely no match for Wei Jun, so Wei Yan proposed to let Han Xin, the marquis of Huaiyin in the Western Han Dynasty, be in Tongguan. Chang 'an is located in Qinchuan, 800 miles east of Wu Tong, which is the throat of Chang 'an leading to the Central Plains. If we can occupy the pass, we can refuse Wei's reinforcements. Chang 'an to Tongguan is160km, which can be reached in three days, while Luoyang to Tongguan is 270km. Tongguan is not in wartime, so it can pass before Wei Jun. More than 20 days later, Gu Jie's Zhuge Liang's soldiers arrived and occupied Puban and Wuguan. At that time, Wei Jun was helpless. " If the Han Dynasty is prosperous, we can wait for one day. ".Even if Wei Yan was completely annihilated, it would only cost thousands of people, which had little effect on Zhuge Liang's army in Gu Jie. Zhuge Liang, on the other hand, believes that "it is better to be content with the truth, to take Longyou equally, and to overcome everything." So, "raise your voice and take punishment from Gu Jie Road, which makes Zhao Yun and Deng Zhi suspicious. According to Ji Gu's "I personally led the army to attack Qishan (now in Lixian County, Gansu Province)", Nan' an, Tianshui and Anding counties rebelled against Wei and Guanzhong shook. " Wei Mingdi led fifty thousand cavalry "ma bu" or horse stance just look straight to the west Chang 'an, and ordered Zhang He to refuse. Zhuge Liang didn't need battle-hardened generals such as Wei Yan and Wu Yi, but he used them against the will of the people. Liu Bei called them "exaggerated and useless". Ma Su was in front of the army, fighting them in the street kiosks, and the result was disastrous. Zhuge Liang had to "pull out more than a thousand households in West County, return them to Hanzhong and kill Xie Zhong." Shu is weak, while Wei Guoqiang is. Only by being brave and good at fighting can we win. Cao Cao burned his lair, and Wargo sneaked into the level ground, which was several times more dangerous than Wei Yan's plan. Liu Bei dared to attack Hanzhong with the soldiers who poured out the country, and then raided Xia with the correct strategy, all of which were his ways of using troops according to the situation. A Qishan shows that Zhuge Liang is not good at military affairs. Sue, he is an armchair strategist and has no mastermind, so he is almost a timid fighter. When Ma Su was beheaded, his ministers advised Zhuge Liang not to do so. After Jiang Wan went to Hanzhong, he said that Liang said, "Chu killed the ministers in the past, and then we can know Qi Huangong's happiness. Don't hesitate to count the wise when the world is undecided! " Zhuge Liang still "killed Xie Zhong". They don't know that hundreds of thousands of people are crying for Ma Su. It is not good for Ma Su to take the lead, but Zhuge Liang despises everyone, and Zhang Heling leads the fine ride, but it is normal to beat him. Moreover, Zhuge Liang's command was wrong, and the two armies were hundreds of miles apart, so there was no time to rescue them. Killing Ma Su was just a diversion by Zhuge Liang, and Ma Su took the blame for the failure of Zhuge Liang's Northern Expedition. After Zhuge Liang's first northern expedition failed, Wei strengthened the defense around Chang 'an, and Zhuge Liang's "revival of the Han Dynasty" became a slogan. Zhuge Liang's departure from Qishan, denial of the meridian valley plan, defiance of the generals and killing Xie Zhong became the basis for his demotion by future generations.