A statue of John Rabe outside his former home in Nanjing
Rabe's house in Nanjing is now a museum and centre for peace studies
"After such a long time, there should be a way of dealing differently with the responsibility they have, rather than trying to avoid it or make it disappear," he says.
John Rabe is expected to be widely viewed in China after it premieres at the Shanghai Film Festival in June. But it is unclear whether the film will be released in Japanese cinemas.
The film's producers hope that the involvement of Japanese star Teruyuki Kagawa will prevent the film from being silenced there.
Teruyuki Kagawa plays the emperor's relative, Prince Asaka, who was the top ranking Japanese officer in Nanjing at the height of the atrocities.
During the Tokyo War Crimes Tribunal in 1946, Prince Asaka denied any massacre of Chinese and said he had never received any complaint about his soldiers' conduct.
Controversially, the film speculates on his involvement in the decision-making process.
Teruyuki Kagawa says: "When faced with this film, many people will be shocked [to learn] the Japanese carried out such cruel acts.
"I think Japanese people will find the two hours very hard [to watch]."
The film recently opened in Germany, and the BBC article noted that
The passage of time has allowed Germany to review its own wartime actions, notably the Nazi genocide of some six million European Jews during World War II.
Now with historical distance, the 37-year-old director hopes the film will trigger a new dialogue and help Japan also come to terms with its own past.
Reddit, a news aggregation site, has a thread about the BBC article that brings up the issue of textbook and history revision debates that are occuring in Japan, especially about issues surrounding WWII.