Though Japan's imperial system is thousands of years old, Japanese emperors had very little power during the 17th,
18th, and 19th centuries. In 1867, a series of events known
as the Meiji restoration returned control of Japan to its
emperor. Powerful Japanese emperors led a
modernization program in Japan that allowed it to become
wealthy and powerful during the 20th century. The
Japanese Empire used its military power to conquer Korea,
Vietnam, parts of China, and other territories in Southeast
Asia during this period. During World War II, Japan fought
as one of the Axis powers but was forced to surrender
after the United States dropped two atomic bombs on
Japanese cities. Though the United States considered
ending the imperial system entirely, it eventually allowed
the emperor to remain in place. However, his power was
greatly reduced, and present-day Japanese emperors serve
ceremonial roles instead of being political leaders.
What is one example of change described in the passage?