By China correspondent Stephen McDonell.
For many people, World War II was the crucial turning point of the 20th century – a key moment in history to be studied and remembered.
However, between Beijing and Tokyo it remains a running sore that is set to be reopened yet again this week.
Japan's prime minister and emperor are both expected to apologise for atrocities committed by the country during World War II.
But in China — where Japan's imperial forces were at their most brutal — deep feelings of resentment linger, and the war remains a source of ongoing diplomatic conflict even today.
The Japanese imperial forces committed many atrocities and war crimes in China, such as when they tested chemical and germ warfare weapons on civilians.
But perhaps the most infamous atrocity is what became known as "the Rape of Nanking".
When Japanese troops arrived in Nanjing, they went on widespread killing spree where hundreds of thousands are thought to have been murdered.
Xia Shuqin, a resident of Nanjing who was eight years old when the Japanese soldiers arrived at her house, remembers the events vividly.
"They held bayonets and rifles. My father was shot dead once he opened the door. They killed him without saying a word," she told the ABC.
"They killed my neighbour, an uncle. My mother was under the table with my little sister. They dragged her out," she said.
"They grabbed the baby and killed her by smashing her onto the ground."
There were 15 family members and neighbours at her home that day — only two would survive.
Ms Xia's grandfather instructed her to hide and she watched her nearest and dearest as they were killed.
"The Japanese soldiers stabbed my mother. They even pounded her body with a rifle. They pulled one of my sisters onto a table and slashed her with a sword," Ms Xia said.
"Then they came for another sister. As they dragged her I tried to hold her back and they stabbed me three times. Then I blacked out. When I woke up only my four-year-old sister was alive."
Only Ms Xia and her little sister survived the massacre.
Every Japanese history book minimising the country's war-time aggression prompts an outcry in China.
Every visit by a Japanese leader to the Yasukuni Shrine — which honours (amongst others) Class A war criminals — prompts a major diplomatic rift.
Japan has officially apologised before – and it will do so again in the coming days – but this does not seem to be enough for China and the government will be closely analysing every word spoken by prime minister Shinzo Abe.
The Chinese Communist Party is accused by some of deliberately stoking ill will towards Japan for political reasons.
But Ms Xia, who has visited Japan six times, now thinks it is time the ordinary people of the two countries should unite outside of government and politics.
This post originally appeared on the ABC and was republished here with full permission.
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