The Tanaka approach

"What had the Chinese laborers done in Japan to make them subject to such inhumane treatment?" asked a descendant during a trip to Japan. He wanted to know what ordinary Japanese thought about the event, and asked Tanaka to get an answer from them.

"His question helped me understand the importance of exchanges between the ordinary people of the two countries," Tanaka said.

As a result, his group set up discussions between the visitors and local people.

The professor has also participated in a non-governmental group that encourages people to reflect deeply on the massacre in Nanjing more than 70 years ago.

In December, the group invited several survivors of the massacre to tour Japanese cities, including Tokyo and Osaka, for face-to-face discussions with ordinary Japanese people about their sufferings and observations.

The guests and their hosts watched a documentary produced by Osaka TV more than 20 years ago that reflected on what has become known as "The Rape of Nanjing". The film was based on secret footage of the carnage, taken by John Magee, a US priest who witnessed the event at first hand.

The documentary shocked the Japanese viewers, who, for the first time, saw film of the massacre.

"As society tilts toward the right, it is impossible for Japan's TV stations to produce films like this one. Even so, there is no chance they could be broadcast," Tanaka said. "But we will create opportunities to allow more people to view it."

Tanaka has devoted himself to presenting a factual account of history by illustrating specific events. By doing so, he wants to enable the Japanese people to be given a truthful historical account.

But it's an uphill battle, especially because Japanese publishing houses and bookstores are winning readers by printing and selling books disparaging China and South Korea.

Some bookstores in Tokyo have set aside special sections for these books.

The comic book series Manga Ken Kan Ryu (Hating the Korean Wave) has sold 1 million copies since its publication in 2005, according to the Asahi Shimbun.

Japan's weekly magazines have begun running a greater number of articles about China since the autumn of 2010 when a Chinese trawler and two Japanese coastguard cutters collided in the waters off the Diaoyu Islands in the East China Sea. Those that print articles with headlines that contain the words "China", "South Korea", "Senkaku" (the Japanese name for the Diaoyu Islands) and "comfort women" sell well.

To observers such as Tanaka, Japan has taken the mantle of "war victim" on itself because it's the only country to have been the target of atomic bombs. It talks a lot about the adversities its people suffered in the war, but blots out the pain and damage its imperial troops committed in other countries.

Conservative politicians frequently argue that Japan was bullied into the war and fought only to liberate Asia from Western imperialism.

"The memories of the atomic bombings, which are only part of the war, are not adequate. The Japanese people should be told the whole picture," Tanaka said.

In 1970, the then-German chancellor Willy Brandt knelt before a monument commemorating the Warsaw Ghetto Uprising. In 2013, Abe saluted his country's war criminals.

Despite Abe's administration allowing the historical issues to fester, Tanaka has chosen to heal the wounds in his conscience, and those of his compatriots.

He still keeps one of the 1,000 yen banknotes with Ito's portrait in his wallet as a constant reminder of a chapter of Japan's history that he will never forget and is determined that other Japanese must acknowledge.