The demise of the Shu kingdom can be said to have been doomed from the moment Zhuge Liang died. Even if the later lord Liu Chan did not surrender the country, in the end he would not be able to save the country at all. Even if Zhuge Liang had not died so early, the Shu state would have been able to survive for a few more years at best, because the Shu state was small and relatively closed, and if it did not expand externally, it would only be able to open up more and more gaps with the enemy country.
Zhuge Liang is indeed a partial talent, he seems to be Xiao He in the early Han Dynasty, and an internal ability is absolutely first-class, but the ability to hold outside is not flattering. In fact, under Liu Bei's account, there was more than one person who was higher than Zhuge Liang in terms of strategy, and in addition to Fazheng and Pang Tong, Xu Shu and Ma Liang were probably not after Zhuge Liang.
The strongest trio of kings in the Shu kingdom were Zhuge Liang, Fazheng, and Pang Tong, who were responsible for stabilizing the rear, raising grain and grass salaries, and developing the domestic economy; Pang Tong was responsible for formulating strategy, responsible for coordinating armaments, and they were also first-class strategists; and Fa Zheng was the best at tactics and good at making strange plans, and the combination of these three people could be said to be invincible. But alas, the three of them didn't seem to have really worked together.
However, even after the death of Pang Tong, in the era when the Fa was shining, the Shu state could be completely invincible. Because one of the biggest disadvantages of the Shu state was the lack of top strategists, which was incomparable with the Wei state. Xu Shu, Pang Tong, Fa Zheng, and Ma Liang, who had served the Shu state successively, either had to leave or died young, so that the Shu state lost the ability to open up territory and expand the territory.
Zhuge Liang was at best able to keep the Shu state from being destroyed, and its ability to open up to the outside world was actually very limited. Therefore, we can see that after Liu Bei's death, the State of Shu can be said to be a withering of talent. Zhuge Liang's many northern expeditions mostly returned in failure, and no substantive breakthroughs were made at all. One of the big reasons for this is because of the lack of talents in the Shu kingdom.
You know, but at the beginning of Liu Bei's conquests, Zhuge Liang was responsible for the transportation of grain and grass in the rear, and Liu Bei never lost the war because of a lack of grain. However, when it was Zhuge Liang's turn to carry out the Northern Expedition, no one was able to do what he did, to maintain the stability of the rear and to continuously transport grain to the front line. Therefore, Zhuge Liang simply could not take care of the end and the end, and later was often forced to withdraw his troops because the lone army was deep in grain and grass.
What's more, Zhuge Liang himself did not have too high a strategy, so his Northern Expedition was also in trouble, and there was no possibility of creating a miracle at all. In fact, in the final analysis, it was because the Shu Kingdom lacked a top strategist, which led to Zhuge Liang's inability to use the same mind as Ben alone, and there was no top person who could help him share his worries.
In other words, if the Fa was right at that time, the Shu Kingdom would never have fallen into this state. Because of the two major defeats of the Shu state, one was because Guan Yu lost the Jingxiang region, which greatly reduced the territory of the Shu state and lost the gateway to the Northern Expedition from the Jingzhou region; the other time was because Liu Bei was defeated at the Battle of Yiling, so that the national strength was greatly damaged, not only the soldiers were almost completely destroyed, but also caused internal contradictions between different groups in the country.
However, if Fa Zheng had not died so early, these two defeats would certainly not have been so complete, and it was even very likely that some results would be achieved, and the national strength of the Shu state would not have been consumed into the smallest country. Therefore, if Fa Zheng had not died young, the Shu Kingdom would not have been so embarrassed by the time of the Later Northern Expedition, and the combination of Zhuge Liang and Fa Zheng would have been very strong in the late Three Kingdoms period.
With Zhuge Liang sitting in Chengdu and stabilizing the rear area, the Shu state would be able to occupy the heavens and the people, and could continuously supply grain and grass to the front, so that the Northern Expedition would be in an active position and would not return because of objective factors. With Fazheng's strategy, if he could command the Northern Expedition on the front line and Take Wei Yan as the vanguard, he would definitely be able to make a difference.
Because Fa Zheng likes to be surprised, and Zhuge Liang is relatively stable, this is also where Fa Zheng is higher than Zhuge Liang as a top strategist. Zhuge Liang was the best at governing the army and sending troops to deploy troops, but he was not very good at marching and fighting. Moreover, he actually lacked the experience of being independent, because in Liu Bei's time, it was Fazheng who followed Liu Bei on the expedition, and Zhuge Liang generally played the role of guarding the portal and logistics.
Therefore, in terms of Fazheng's military ability, the combination of the two can definitely have enough ability to open up to the outside world, even if it cannot pacify the north, but it can definitely make itself invincible. Under the condition of ensuring the security of the Shu state, it is possible to encroach on the land of the Wei state little by little, cultivate both inside and outside, and strengthen the strength of the Shu state. With the rugged terrain of the Shu Kingdom and Zhuge Liang's ability to conduct internal affairs, it was absolutely impossible for the Shu State to surrender as it did later.