Take your moral outrage somewhere else. the Chinese theater was largely irrelevant to the rest of the war. And where would those Japanese troops gone the would have been useful? Oh that's right they would have gone to southeast Asia where needing more troops wasn't an issue and they just would have got cut off from supply later anyway.
That's false.
A lot of supplies went into the Chinese theater that could have been used elsewhere, Japan had little industry, just like in the www, daniel spent a lot of resources on the Chinese front.
I could go on, but it should be obvious to everyone that if China capitulated and Japan no longer had to maintain a war in China, and got all those resources, the dynamic in the pacific would change immensely.
Japan went to war with the United States because of the war in China.
I posted this elsewhere, but the following stats cost Japan resources, money, time, energy and lastly led to the confrontation between Japan and the West.
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In 1937, at Shanghai, there was a 3 month battle. The Chinese state (KMT) had 700,000 soldiers, 250 airplanes and 16 tanks involved in this battle. The opposing Japanese had 300,000 soldiers, 3000 airplanes, 300 tanks, and 130 naval ships. At the end of the battle, KMT forces suffered 283,500 casualties, while Japan suffered only 92,640.
Fast-forward to March 1938, Japanese forces tried to encircle Nationalist forces at Xuzhou. 600,000 Chinese state forces fought against 240,000 Japanese troops. Chinese forces managed a breakthrough and escaped intact, suffering 100,000 casualties, vs 30,000 Japanese casualties.
Look at the Battle of Tai'erzhuang (1938), where the Chinese government won a decisive victory against Japan. In this battle Chinese government forces were 400,000 versus 70,000 Japanese troops.
In June 1938, a 4 month battle began as the Japanese attempted to crush the Chinese government at the battle of Wuhan. During this battle, the Chinese government forces numbered 1,100,000 troops, 300 planes, and 50 ships, versus 350,000 Japanese troops, 500 planes, and 120 ships. Chinese forces lost 400,000 from casualties, while Japan lost 140,000.
Battle of Changsha (1939), Chinese government forces numbering 240,000 defeated a Japanese force attempting to capture the city, numbering 100,000. Chinese government forces suffered 40,000 casualties, Japanese forces suffered 40,000+ casualties.
Battle of South Guangxi (1939-1940) 150,000 Chinese government forces defeated 100,000 Japanese troops.
1939–40 Winter Offensive, Chinese Nationalist forces launch a full scale offensive against Japanese occupation forces. The Nationalist Army attacks with 550,000 troops, against 850,000 Japanese troops. This is a Nationalist defeat.
Battle of Changsha (1941) - 110,000 Chinese troops defeat 120,000 Japanese troops, attempting to capture Changsha, a second time. These are government troops, fighting a centralized war effort.
Battle of Changsha (1942) - 300,000 Chinese troops defeat 120,000 Japanese troops, again. This time the Japanese lose all 600 pieces of artillery they brought with them, and suffer 56,746 casualties. The Chinese suffer only 28,116 casualties. The third attempt to capture Changsha is a failure.
China's government sends two armies to Burma to help the British defend against Japan (1942). Britain loses Burma. These two armies are virtually destroyed.
Battle of Northern Burma and Western Yunnan (1943-1945) 400,000 Chinese troops fight 150,000 Japanese and Thai troops, to recapture Northern Burma and Western Yunnan. Allied victory.
Battle of Changde (1943) 210,000 Chinese troops defeat 100,000 Japanese troops attempted to capture Changde. Japanese forces suffer 40,000 casualties. China suffers 60,000 casualties.
Operation Ichi-Go (1944), Japan launches a massive offensive against the Chinese government positions. Chinese forces number 1,000,000 troops, against 500,000 Japanese troops, 6000 artillery pieces, 800 tanks, and 150,000 vehicles. China loses the campaign, suffering 750,000 casualties, and 6,723 artillery pieces. Japan loses 100,000 men.
During the height of this battle, China's government sends its best troops to Burma to help the British fight against Japanese forces there, in order to re-open the Burma road.
Following the Ichi-Go campaign, China launches a counter attack. Battle of West Hunan (1945), 200,000 Chinese troops against 80,000 Japanese troops. Allied victory.
Second Guangxi Campaign (1945), 600,000 Chinese troops defeat 660,000 Japanese troops, and China pushes Japan out of Southern China.
Significant front that affected the world war significantly, if we consider Japan to be a significant actor in the world war. Without this never-ending war, Japan found itself stuck in, unable to set up a larger puppet government or find a cease-fire, Japan spent more and more resources into the China war black-hole. The more the war waged on, the more popular opinion about Japan fell, Japan became so tunnel visioned on forcing a Chinese peace that they went to war with the West to pursue that goal.
Its fairly obvious the Chinese front was important. It's not only about what China did, but what could have happened if China gave up.