International politics is always shifting, basically affected by changes in the balance of power. Of all the factors that can change a balance of power, one that is unique to modern international society (since the 19th century) is the economic growth of a single country.
Unlike the classic examples of a power-change, such as the annexation of territories or the formation of alliances, an economic change is invisible to the outside world, and it is hard to determine the point in time when a country begins presenting itself as a growing threat.
China has had a bitter experience in Asia. The Ching dynasty, which had its eyes opened following the Opium War, reorganized the nation and proudly built a formidable North Sea Fleet. However, it failed to realize how rapidly Japan had risen since the Meiji Restoration of 1868 and did not change its perception of Japan as a minuscule state until the year before the Sino-Japanese war (1894-5). That resulted in its defeat in that war, the intervention of Western imperialistic powers, and its semi-colonization over the next several decades.