Zhuge Liang's Northern Expeditions - Analysis

Analysis

It is surprising that although, of the three states, Shu was the weakest in terms of land size and resources, in its early years it carried out a vigorous offensive military policy. If Zhuge Liang had not died in 234, he may well have continued this policy. However, the constant expeditions took a heavy toll on Shu's limited resources and this was worsened by Jiang Wei's Northern Expeditions after the death of Zhuge Liang. Resources wise, Shu was far inferior to the vast state of Wei, as reflected in the obvious numerical difference: with the exception of the second expedition, Shu force committed never exceeded 50% of the Wei force it faced during each campaign, and it was only Zhuge Liang's ingenuity that forced Wei to be on the defensive all the time.

Sima Yi was arguably one of the best tacticians that Wei had at that period. Even so, after initial defeats against Zhuge Liang, he was forced to change his tactics in the later expeditions. He was on the defensive for long periods of time with strong fortifications to deter Shu. His aim was to create a deadlock in which was to wait for Shu's supplies to run out and to force them to retreat without a fight. In the last expedition's deadlock on the Wuzhang Plains, Sima Yi's reluctance to engage in battle prompted Zhuge Liang to send him a woman's dress in one occasion to mock his tactics. Even so, Sima Yi refused to rise to the bait, much to the displeasure of his officers.

The diplomatic success in restoring the alliance with Sun Quan prior to the Northern Expeditions has been dismissed as useless because it brought little strategic dividend: each side had different political agendas which precluded close military coordination. Once the first Northern Expedition was turned back, the Wei state was capable of handling the two-front threat without much difficulty.

Arguments revolving around Wei Yan's plan for a surprise assault on Chang'an have never been stopped. Whether his plan could have succeeded, Zhuge Liang had rejected it, believing the plan was far too ambitious. In Zhuge's view, Chang'an, being one of Wei's most prosperous cities, would probably have been well fortified, in contrast to the intelligence from Wei Yan. Furthermore, there is little chance that the people of the city, who enjoyed peace and prosperity under the rule of Wei, would side with the Shu-Han forces. However, it may be more possible that Zhuge's military objective was to cut the connection between Longyou and Luoyang to force the surrender of the western wing of Wei, instead of attacking the heartland of Wei to "restore the Han Dynasty".