Russo-Japanese War: The Early 20th-Century War That Shocked the World and Led to Japanese Imperialism

The strategic significance of Korea in the emerging conflict cannot be overstated, as the peninsula represented both a gateway to China and a potential threat to Japan's security depending on which great power controlled it. For Japan, Korean independence or, failing that, Japanese influence over Korea was essential to prevent a hostile power from establishing bases within striking distance of the Japanese home islands. The geographic proximity of Korea to Japan meant that any major European power controlling the peninsula could threaten Japan's maritime communications and potentially launch an invasion, making Korean independence a matter of existential importance for Japanese security planners. Russia's growing influence in Korea following the Sino-Japanese War of 1894-1895 therefore represented an intolerable threat that Japanese leaders believed could only be resolved through diplomatic agreement or military action.