Early in the period of united resistance, the government permitted the New Fourth Army to be created from remnants of communist troops left in Jiangxi and Fujian at the time of the Long March. Commanded by Gen. Ye Ting—with Xiang Ying, a communist, as chief of staff—this force of 12,000 officers and soldiers operated behind Japanese lines near Shanghai with great success. Its strategy included guerrilla tactics, organizing resistance bases, and recruitment. This army grew to more than 100,000 in 1940; by then it operated in a wide area on both sides of the lower Yangtze.
Thus the CCP revitalized itself. It recruited rural activists and patriotic youths from the cities and systematically strengthened its ranks by continuous indoctrination and by expelling dissident and ineffective party members.
Renewed communist-Nationalist conflict
There were numerous clashes between communists and Nationalists as their military forces competed for control of enemy territory and as the communists tried to expand their political influence in Nationalist territory through propaganda and secret organizing. Though both sides continued the war against Japan, each was fighting for its own ultimate advantage. Bitter anticommunist sentiment in government circles found its most violent expression in the New Fourth Army Incident of January 1941.
Chiang Kai-shek meeting with his staff during the Sino-Japanese War (1937–45).Encyclopædia Britannica, Inc.
The government had ordered the New Fourth Army to move north of the Huang He (Yellow River) and understood that its commanders had agreed to do so as part of a demarcation of operational areas. However, most of the army had moved into northern Jiangsu (south of the Huang) and, together with units of the Eighteenth Army Group, was competing with government troops for control of bases there and in southern Shandong. Ye Ting and Xiang Ying stayed at the army’s base south of the Yangtze. Apparently believing that Ye did not intend to move northward, government forces attacked the base on Jan. 6, 1941. The outnumbered communists were defeated, Ye Ting and some 2,000 others were captured, Xiang Ying was killed, and both sides suffered heavy casualties. Ignoring Chiang Kai-shek’s order to dissolve the New Fourth Army, the communist high command named Chen Yi as its new commander and Liu Shaoqi as political commissar.
The danger of renewed civil war caused widespread protest from China’s civilian leaders. The People’s Political Council, a multiparty advisory body formed in 1938 as an expression of united resistance, debated the issue and later tried to mediate. Neither the KMT nor the CCP was willing to push the conflict to open civil war in 1941. The government deployed many of its best divisions in positions to prevent the communist forces from further penetration of Nationalist-held territories and to weaken the CCP through a strict economic blockade.
The international alliance against Japan
The United States had broken the Japanese diplomatic code. By July 1941 it knew that Japan hoped to end the undeclared war in China and that Japan was preparing for a southward advance toward British Malaya and the Dutch East Indies, planning to first occupy southern Indochina and Thailand, even at the risk of war with Britain and the United States.
U.S. aid to China
One U.S. response was the decision to send large amounts of arms and equipment to China, along with a military mission to advise on their use. The underlying strategy was to revitalize China’s war effort as a deterrent to Japanese land and naval operations southward. The Nationalist army was ill-equipped to fight the Japanese in 1941. Its arsenals were so lacking in nonferrous metals and explosives that they could not produce effectively. The maintenance of millions of ill-trained and under-equipped troops was a heavy drain on the economy. There was no possibility that the United States could arm such numbers from its limited stocks while building up its own forces and assisting many other countries. In addition, there was a formidable logistics problem in shipping supplies along the 715-mile (1,150-km) Burma Road, which extended from Kunming to Lashio, the terminus in Burma of the railway and highway leading to Rangoon.
By December 1941 the United States had sent a military mission to China and had implicitly agreed to create a modern Chinese air force, maintain an efficient line of communications into China, and arm 30 divisions. Japan’s bombing of Pearl Harbor in Hawaii brought the United States into alliance with China, and Great Britain joined the Pacific war as its colonial possessions were attacked. This widening of the Sino-Japanese conflict lifted Chinese morale, but its other early effects were harmful. With the Japanese conquest of Hong Kong on December 25, China lost its air link to the outside world and one of its principal routes for smuggling supplies. By the end of May 1942, the Japanese held most of Burma, having defeated the British, Indian, Burmese, and Chinese defenders. China was almost completely blockaded. For the moment, there was little China’s allies could do other than state a willingness to offer China loans.
The solution was found in an air route from Assam, India, to Kunming, in southwest China—the dangerous “Hump” route along the southern edge of the Himalayas. In March 1942 the China National Aviation Corporation (CNAC) began freight service over the Hump, and the United States began a transport program the next month. But shortages and other difficulties had to be overcome, and not until December 1943 were cargo planes able to carry as much tonnage as was carried along the Burma Road by trucks two years earlier. This was much less than China’s needs for gasoline and military equipment and supplies.
Conflicts within the international alliance
China’s alliance with the United States and Great Britain was marked by deep conflict. Great Britain gave highest priority to the defeat of its main enemy, Germany. The U.S. Navy in the Pacific had been seriously weakened by the Japanese air attack at Pearl Harbor and required many months to rebuild. During the winter of 1941–42, the grand strategy of the United States and Great Britain called for the defeat of Germany first and then an assault across the Pacific against Japan’s island empire. China was relegated to a low position in U.S. strategic planning. The United States aimed to keep China in the war and enable it to play a positive role in the final defeat of Japan on the continent. Chiang Kai-shek, on the other hand, envisaged a joint strategy by the United States, the British Commonwealth, and China over the whole Pacific area, with China playing a major role. He demanded an equal voice in Allied war planning, which he never received, though U.S. President Franklin D. Roosevelt was generally solicitous. From the fundamentally different outlooks of Chiang, British Prime Minister Winston Churchill, and Roosevelt and because of the divergent national interests of China, the British Commonwealth, and the United States, there followed many controversies that had powerful repercussions in China and led to frustrations and suspicions among the partners.