Prime Minister Mitsumasa Yonai speaking with war orphaned children in his home town, 1940 (via: World War II Database)
In 1940, after Nationalist Chinese victories in Changsha and Guangxi, and with her lines of communications stretched deep into the Chinese interior, Japan had reached a stalemate in the war with China. Although the Japanese ruled the large cities, they were unable to control the countryside. Japanese forces were also unable to defeat the Chinese communist guerilla forces in the Shaanxi province.
Thus Japan was unable to achieve complete victory and China was unable to expel Japan from captured territory.
Japanese occupation 1940; Wikimedia Commons