However, European countries which started to explore the world after the Age of Geographical Discovery to expand their areas of dominance and the USA which rode on the wave of continuous Imperialism and made a foray into Africa and Asia for incursions and colonization became a threat for East Asian countries.
ところが大航海時代以降世界に進出、支配領域を拡大したヨーロッパ、続く帝国主義の波に乗ったアメリカ合衆国によるアフリカ・アジア進出・侵略・植民地化は、東アジア各国にとっても脅威となった。