1930s: In the Chinese city of Nanking, invading Japanese troops kill an estimated 369,366 Chinese civilians and prisoners of war between December 1937 and March 1938. About 80,000 women and girls are raped; many are then mutilated and murdered.

Today: For decades Japan refused to apologize to China for atrocities committed during World War II. In 2005, Japanese prime minister Junichiro Koizumi apologizes for the fact that Japan caused grief and pain to many people in Asian nations during the war. But he does not mention Nanking by name.

1930s: China is under the rule of the Nationalist Party, led by Chiang Kai-shek. The Chinese Communist Party opposes the nationalists but in the 1930s is on the defensive. In 1934, the communists begin their famous 6,000-mile Long March from Hunan to northwest China, where they establish a base.

Today: China is ruled by the Communist Party, but economic reforms over...