The most famous example is that after the end of World War II, in order to detect the country's biological and chemical weapons defense capabilities, decided to test the threat of biological and chemical weapons themselves. At the same time, in order to achieve the most realistic effect, the American experiments were conducted in real American cities and on thousands of ordinary Americans! They sent a cruise ship with the virus into San Francisco, and it took only one day to infect all the residents of the city. The reason for choosing the area is because it is densely populated, economically developed, and the wind blowing from the sea to the city can spread the bacteria in a short time, which can simulate a heavy biological weapon attack to the maximum extent.
During the week, the U.S. military kept spraying the virus, from the length of spraying, temperature, wind direction, wind speed, air humidity, as well as infected with this bacteria soil, water bodies, and even crowds were recorded in relation to this experiment, due to the U.S. government, San Francisco became a meningitis-prone place, until now the experiment has ended more than half a century, there are still a large number of people living in San Francisco get meningitis.
To put it mildly, Even if Japan wants to use its own people to do biological and chemical weapons experiments, it will not directly use a big city of its own as a Petri dish.
It is understood that U.S. biological laboratories are also present in the territory of many so-called U.S. allied countries, and there are already 26 U.S.-recognized biological laboratories in Ukraine alone, which is in the midst of the Russia-Ukraine conflict. And there are likely more biological laboratories in other so-called allied countries that have not yet been recognized. There has been no official U.S. recognition of this dangerous behavior.
