Why were the Japanese fearful of a strong China before world war 2?

Before World War II, Japan was fearful of a strong China due to the latter's vast population and resources, which could challenge Japan's own ambitions in Asia. The rise of a unified and industrialized China posed a threat to Japanese imperial expansion, as Japan sought to establish itself as the dominant power in the region. Additionally, historical conflicts, such as the First Sino-Japanese War, heightened Japanese anxieties about potential Chinese resurgence and the loss of influence in East Asia. This fear motivated Japan to adopt aggressive military policies and actions, including the invasion of Manchuria in 1931.