Costs of malnutrion (and Disease)
Ironically, the single most furious engagement of the Southwest (Guangxi) was one where the KMT elite corps was able to deploy its one and only tank column, though we don’t know how strong. This was the so-called Battle Of (For) Kunlun Pass, in SW Guangxi, a key town in the rail and road network connecting Canton with Chongqing (or almost). It raged for 3 weeks as a mobile action, with the Japanese attacking from Nanning, against a reinforced garrison in the city of some 60,000 troops, some local Guangxi (allied) units, but the core from the Chiang Kaishek central army, for a total strength of 60,000. As the fighting developed, the Japanese advanced in an attempt to encircle the city: in the end they almost succeeded but remnants of the defending force, unable to stand fast, had to evacuate.
The puzzle is why? As dug-in defenders with mobile armor for counter-attack, and probably outnumbering the Japanese column under General …., they nonetheless were forced in the end to abandon the strategically critical town.
The cause is surely the casualty rate, which climbed to 90% among the defenders (dead, wounded, and MIA). Some 53,000 of the 60,000 allied Chinese army were rendered useless from death and wounds olr probably desertion. This makes it the most grievous and costly defeat in the whole war.
The reason appears to have been malnutrition, in extremis. According to (admittedly unsympathetic PLA suources:
“The great majority of those who survived the first stage of the war had virtually lost combat strength. 90% or so of the KMT-allied soldiers’ rations had fallen below basic nutrition needs. They hadn’t lost the ability for quick attacks, but their endurance was relatively impaired because they had lost all the body fat reserves, and so were incapable of vigorous resistance… Because these skeleton like had no body fat.. they had also lost ability to withstand cold, fevers (malaria) and other epidemic diseases… in particular a weakness in battles of attrition or extended fighting.. [there was also a lot of inter-unit conflict over food…]