Japanese Prime Minister Sanae Takaichi has sparked an international furor with her statement in parliament on Nov 7 suggesting that Japan might use military force if a "Taiwan contingency" leads to a "survival threatening" situation. Her remark crossed a red line of China and underscored concerns about Japan ramping up remilitarization, which would effectively violate the Article 9"no-war clause" of the nation's postwar Constitution.

From my perspective, though, as a longtime researcher and writer of Imperial Japan's chemical and germ warfare attacks against China, the matter of Japan's military launching a future invasion of China appears somewhat redundant. The lingering presence in Chinese land of biological weapons and discarded poison gas bombs, which were used by the occupying Imperial Japanese Army during the 1930s and 1940s, amounts to a broad vector of destruction to the Chinese populace stretching from past to present — a large-scale, armed attack whose impact has never ended.

On Aug 20, 1945, five days after Japan surrendered, and as the Soviet Army approached, the personnel of Unit 100, a branch of the infamous Unit 731, set loose thousands of plague-infected rats from their enclosures in the death factory. The rodents swarmed over the region, causing lethal human epidemics in Changchun, the capital of Northeast China's Jilin province, and nearby villages in 1946 and for years afterward.

Unit 731 also spread anthrax bacteria in parts of Northeast China.

Furthermore, the Japanese Army used chemical weapons on a frequent basis, both in combat and against civilians, despite Japan's ratification of the 1899 Hague Convention banning poisonous arms. Upon Japan's surrender, they left behind some 2 million such weapons in undisclosed burial sites and rivers throughout China. Unexploded chemical bombs have been found in more than 40 locations. The poisons of mass destruction — phosgene, lewisite and mustard gas among them — have killed or maimed with an ageless horror the unsuspecting Chinese men, women and children who unearthed them.

Japanese teams have been helping with the finding and disposal of the poison gas shells and canisters, as per a United Nations treaty obligation. Yet as of July 2006, Chinese officials were complaining of their slow pace, and the Japanese workers said they were short-staffed and needed more money from the Tokyo government.

China has noted that more than 2,000 people have died from the chemical weapons they accidentally uncovered. A 2007 deadline for the destruction of all the weapons was extended to 2012, and, as of this year, an enormous quantity of the abandoned shells, canisters and contaminated materials continues to pose a lurking threat to people just going about their daily routines.

In December 1999, I attended a Tokyo conference on the history of the Unit 731 network's 1931-45 biological warfare and biological death-lab prisons. Academics, journalists and surviving Chinese victims of Japanese germ attacks were among the conference participants. The surviving victims were engaged in a lawsuit for reparations from Japan for the deaths of family members and neighbors and the severe illness that they themselves endured from the Japanese military doctors' methodical spreading of virulent disease. The court case gathered momentum with a great deal of testimony from 180 plaintiffs and expert opinion from historians.

In 2002, with tragic predictability, a Tokyo court handed down a verdict denying all claims for restitution for the victims. Other compensation lawsuits filed by Chinese victims of Japanese war crimes, including the Nanjing Massacre, the use of "comfort women" (those forced into sex slavery), and the abandoned chemical weapons, have all been dismissed by Japan's legal system.

Postwar Germany has long acknowledged the nation's Holocaust crimes and the evil of other Nazi war crimes, and has, in many cases, compensated victims. In contrast, Berlin's World War II Axis partner Japan continues to whitewash history textbooks and brush off the lawsuits of its Asian victims, even though its atrocities are well documented and have been recorded in court proceedings.

Adding to the agony of the victims of Japanese military atrocities and their families in Asia and other places, Japanese Prime Minister Takaichi has frequently visited the Yasukuni Shrine, which honors, among Japan's war dead, more than a dozen Class A war criminals.

On the first day of this year's autumn festival, Takaichi did not visit the shrine as she had on the previous autumn festival and on the anniversary of Japan's surrender in World War II. But she did bestow a ritual offering to the shrine.

And now, with Takaichi at the helm, Japan backslides further, from denial of its wartime past into a renascence of it — even as the Imperial Japanese Army's "unconventional warfare" assaults, in an unbroken thread, still menace the people of China.

An Aug 13 article in the Japanese newspaper Asahi Shimbun said that "while acknowledging the existence of Unit 731, the government has neither confirmed nor denied its activities, such as human experimentation, citing lack of documentation".

It added that, in March, when the unit's atrocities were raised in the Diet, Japan's parliament, then prime minister Shigeru Ishiba said, "The means (to verify the facts) have been lost with history."

The author is an independent historian specializing in Northeast Asia and author of A Plague Upon Humanity: The Secret Genocide of Axis Japan's Germ Warfare Operation. The views do not necessarily reflect those of China Daily.