Joshua A. Fogel, at York University, argued that the book is "seriously flawed" and "full of misinformation and harebrained explanations." He suggested that the book "starts to fall apart" when Chang tries to explain why the massacre took place, as she repeatedly comments on "the Japanese psyche", which she sees as "the historical product of centuries of conditioning that all boil down to mass murder" even though in the introduction, she wrote that she would offer no "commentary on the Japanese character or the genetic makeup of a people who could commit such acts". Fogel asserted that part of the problem was Chang's "lack of training as a historian" and another part was "the book's dual aim as passionate polemic and dispassionate history". David M. Kennedy, a Pulitzer Prize-winning professor of history at Stanford University, also pointed out that while Chang noted that "this book is not intended as a commentary on the Japanese character," she then wrote about the "'Japanese identity'—a bloody business, in her estimation, replete with martial competitions, samurai ethics, and the fearsome warriors' code of bushido", making the inference that "'the path to Nanking' runs through the very marrow of Japanese culture." Kennedy also suggested that "accusation and outrage, rather than analysis and understanding, are this book's dominant motifs, and although outrage is a morally necessary response to Nanjing, it is an intellectually insufficient one." Roger B. Jeans, professor of history at Washington and Lee University, referred to Chang's book as "half-baked history", and criticized her lack of experience with the subject matter:
In writing about this horrific event, Chang strives to portray it as an unexamined Asian holocaust. Unfortunately, she undermines her argument—she is not a trained historian—by neglecting the wealth of sources in English and Japanese on this event. This leads her into errors such as greatly inflating the population of Nanjing (Nanking) at that time and uncritically accepting the Tokyo War Crimes Tribunal and contemporary Chinese figures for the numbers of Chinese civilians and soldiers killed. What particularly struck me about her argument was her attempt to charge all Japanese with refusing to accept the fact of the 'Rape of Nanking' and her condemnation of the 'persistent Japanese refusal to come to terms with its past.' 
Jeans continued what he calls "giving the lie to Iris Chang's generalizations about 'the Japanese'" by discussing the clashing interest groups within Japanese society over such things as museums, textbooks, and war memory.
Robert Entenmann, professor of history at St. Olaf College, criticized the work on the grounds that the "Japanese historical background Chang presents is clichéd, simplistic, stereotyped, and often inaccurate." On Chang's treatment of modern Japanese reaction to the massacre, he writes that Chang seemed "unable to differentiate between some members of the ultranationalist fringe and other Japanese", and that "her own ethnic prejudice implicitly pervades her book." Stating that Chang's description of the massacre is "open to criticism", Entenmann further commented that Chang "does not adequately explain why the massacre occurred".
Timothy M. Kelly, professor at Edogawa University, described Chang's work as exhibiting "simple carelessness, sheer sloppiness, historical inaccuracies, and shameless plagiarism." Kelly further criticized Chang for her "lack of attention to detail".[note 1] Finally, Kelly charged that Chang had plagiarized passages and an illustration from Japan's Imperial Conspiracy by David Bergamini.
Kennedy criticized Chang's accusation of "Western indifference" and "Japanese denial" of the massacre as "exaggerated", commenting that "the Western world in fact neither then nor later ignored the Rape of Nanking", "nor is Chang entirely correct that Japan has obstinately refused to acknowledge its wartime crimes, let alone express regret for them." Chang argues that Japan "remains to this day a renegade nation," having "managed to avoid the moral judgment of the civilized world that the Germans were made to accept for their actions in this nightmare time." However, according to Kennedy, this accusation has already become a cliché of Western criticism of Japan, most notably exemplified by Ian Buruma's The Wages of Guilt (1994), whose general thesis might be summarized as "Germany remembers too much, Japan too little." Kennedy pointed out that a vocal Japanese left has long kept the memory of Nanking alive, noting the 1995 resolution of Japan's House of Councillors that expressed "deep remorse" (fukai hansei) for the suffering that Japan inflicted on other peoples during World War II and clear apologies (owabi) for Imperial Japan's offenses against other nations from two Japanese Prime Ministers.
Sonni Efron of the Los Angeles Times warned that the bitter row over Iris Chang's book may leave Westerners with the "misimpression" that little has been written in Japan about the Nanjing Massacre, when in fact the National Diet Library holds at least 42 books about the Nanjing massacre and Japan's wartime misdeeds, 21 of which were written by liberals investigating Japan's wartime atrocities. In addition, Efron noted that geriatric Japanese soldiers have published their memoirs and have been giving speeches and interviews in increasing numbers, recounting the atrocities they committed or witnessed. After years of government-enforced denial, Japanese middle school textbooks now carry accounts of the Nanjing massacre as accepted truth. Fogel also writes: "Dozens of Japanese scholars are now actively engaged in research on every aspect of the war.... Indeed, we know many details of the Nanjing massacre, Japanese sexual exploitation of 'comfort women,' and biological and chemical warfare used in China because of the trailblazing research" of Japanese scholars.
San Francisco Chronicle staff writer Charles Burress wrote that Chang's quote of a secret telegram sent by Japan's foreign minister in 1938 was incorrectly cited as "compelling evidence" that Japanese troops killed at least 300,000 Chinese civilians in Nanjing. According to Burress, the figure of 300,000 Chinese civilians killed actually came from a message sent by a British reporter, concerning deaths not only in Nanjing but in other places as well. Additionally, Burress questioned Chang's motivation for writing the book - whether she wrote it as an activist or as a historian, stating that the book "draws its emotional impetus" from her conviction to not let the Nanking Massacre be forgotten by the world. Burress also cited Ikuhiko Hata, a Japanese history professor at Nihon University, who argued that 11 photos in the book were misrepresented or fake. One particular photo shows women and children walking across a bridge with Japanese soldiers, and captioned as "The Japanese rounded up thousands of women. Most were gang-raped or forced into military prostitution." Hata stated that the photo originally appeared in 1937 in a Japanese newspaper as part of a series of photos that showed peaceful scenes of Chinese villagers under Japanese occupation.
Chang responded to Charles Burress's criticism in a letter written to the San Francisco Chronicle, but the letter was not published by the newspaper. In the letter, she offered criticism of her own concerning Burress's article. Chang found a "disturbing tendency" by Burress to quote right-wing Japanese critics "without demanding evidence to back up their allegations". She argued that Ikuhiko Hata, a source cited by Burress, was not "regarded as a serious scholar" in either Japan or in the U. S., because he was a regular contributor to "ultra right-wing" Japanese publications. One such publication had published an article from a Holocaust denier that argued that no gas chambers were used in Germany to kill Jews. This caused the parent publisher to shut down the publication. On Burress's criticism of her inaccurate photo captioning, Chang disputed the contention that the caption was wrong. She wrote that her book dealt with the "horror of the Japanese invasion of China", and that the caption reading "The Japanese rounded up thousands of women. Most were gang-raped or forced into military prostitution" contained two statements of indisputable fact.
Chang also issued a rejoinder to Burress's argument that she incorrectly cited a telegram sent by Japan's foreign minister. She wrote that while the original figure of 300,000 Chinese civilian deaths in Nanjing was reported by a British reporter, this figure was cited in a message that Japan's foreign minister sent to his contacts in Washington, DC. Chang argued that figure's use by a high-ranking Japanese government official was evidence that the Japanese government recognized 300,000 as the number of Chinese civilian deaths. Finally, she criticized Burress for his "nitpick" of small details in order to draw attention away from the scope and magnitude of the Nanking Massacre, writing that such was a "common tactic" of Holocaust deniers.