Emperor Emeritus Akihito, marking his 90th birthday on Dec. 23, spends his days like retirees the world over reflecting on the past and trying to lead as normal a daily life as possible.

China repeatedly requested that Emperor Akihito visit after he ascended the Chrysanthemum Throne in 1989. Diplomatic documents released by the Foreign Ministry on Dec. 20 stated that on Dec. 17 ...