Why did Zhuge Liang's 5 Northern Expeditions all end in failure? In the final analysis, it was due to his conservative strategic mentality, because the Northern Expedition "could not be won without a miracle."
First of all, the Shu Han dynasty was originally a weak side relative to the State of Wei, although Sichuan was known as the "Country of Heaven", but the population was only 1/4 of the State of Wei, and the production of people in ancient times was the key, besides, the Territory of the State of Wei was larger, the land was more plain, so the production of grain was naturally more, and the significance of grain production to the war was self-evident.
Secondly, the border between the Shu Han and the State of Wei was roughly near the Qin Mountains, the lofty mountains were easy to defend and difficult to attack, and the State of Wei occupied the heavens and places, so it was naturally more advantageous to wait for work. In the sixth year of Jian'an, the Han army besieged the small Chen Cang, and could have besieged the city to cut off the grain of Chen Cangcheng, at that time it would certainly not attack itself, but due to the difficulty of the Han army's grain supply, it could only retreat in the end, which shows how much the geographical disadvantage affected the Shu Han army.
Therefore, the national strength can not consume the State of Wei, the geographical advantage is not on his side, Zhuge Liang must use a strategy if he wants to succeed in the Northern Expedition, but this is the shortcoming of Kong Ming. The "Romance of the Three Kingdoms" has a sentence about Zhuge Liang that is "Gai Strain will be slight, not his strength!" This means that strain and strategy are not Zhuge Liang's strengths.
Kong Ming not only could not think of a "strange plan" himself, but even the "strange plan" that the general came up with was vetoed. Wei Yan had suggested that han Xin emulate the "Ming Xiu Zhan Dao Darkness Chen Cang" at that time, and lead thousands of elite soldiers out of the Meridian Valley to attack Chang'an, zhuge Liang out of the Valley, and the two sides met at Tongguan, which was the historical "Meridian Valley Conspiracy", but Kong Ming thought that this move was too risky, so he did not accept it.
Therefore, the overall situation at that time was that using a strange plot was not necessarily successful, but not using a strange plan must not be successful, Zhuge Liang did not realize this, still steadily marched and deployed troops step by step, is this not a chronic death? On the contrary, the final result was that Wei Guo Deng Ai used the strange plot of "secretly crossing Yin Ping" to destroy Shu Han, which is ironic to think of.