At this point in time, it was known by Korean military planners that the most powerful inhabitants of Tsushima were away on voyages to Ming China and elsewhere, and moreover as the invasion was launched they ordered the simultaneous internment of all Japanese merchants living and operating within Korea, revealing how carefully they had planned this assault to take advantage of the weakness of Tsushima's defensive preparations and target the general population (not only the Wako).
この時期は対馬の有力者が明などに渡航し不在であることを知り、また同時に朝鮮国内の在留商人らを一斉に抑留するなど、防備の弱体に乗じ一般民衆を標的にした周到な計画であったことが知られる。