In late nineteenth century, Japan started its own invasive action toward neighboring East Asian countries. “It plunged into the Sino-Japanese War in 1894, then into the Russo-Japanese War in 1904 and Japan's annexation of Korea in 1911 successively. In less than a decade from the domination of Korea, Japan entered itself in another large-scale war, World War I, which ended with the victory of Japan's largely Western military alliance.

Invasion and expansion were at the core of Japanese foreign policy in the early twentieth century. During this period, Japan's invasions of neighboring countries resulted in massive land seizure by Japanese military forces and their domination of peoples residing in newly acquired territories. Extensive use of science and technology, together with the development of heavy industries, provided the foundation for construction of military arsenals and high-technology weapons. To the world in the early twentieth century, Japan was a rapidly emerging state that would soon rank with advanced Western powers.

It was in this context that Japan's aspiration to a stronger military presence led the country to participate in another war, this time World War II, the biggest war mankind has ever experienced.

In the World War II, Japan lost. Not only did it lose the war, but it did so devastatingly – as exemplified by the total destruction of the cities of Hiroshima and Nagasaki by the US atomic bombs. The bombs turned two beautiful local-capital cities into barren lands, claiming to this date the death of more than 500,000 just in these two cities.