We heard about it 20 years ago in fact, but it may have sounded technologically implausible. 20 years ago.

https://americanbuddhist.net/2020/03/24/the-secret-speech-of-general-chi-haotian/

https://jrnyquist.blog/2019/09/11/the-secret-speech-of-general-chi-haotian/

https://archive.is/oHzpp

Below is an excerpt from the linked speech, sometime prior to 2003, acquired by Epoch Times in 2005.

To resolve the issue of America we must be able to transcend conventions and restrictions. In history, when a country defeated another country or occupied another country, it could not kill all the people in the conquered land because back then you could not kill people effectively with sabers or long spears, or even with rifles or machine guns. Therefore, it was impossible to gain a stretch of land without keeping the people on that land. However, if we conquered America in this fashion, we would not be able to make many people migrate there.

Only by using special means to “clean up” America will we be able to lead the Chinese people there. This is the only choice left for us. This is not a matter of whether we are willing to do it or not. What kind of special means is there available for us to “clean up America”?

Conventional weapons such as fighters, canons, missiles and battleships won’t do; neither will highly destructive weapons such as nuclear weapons. We are not as foolish as to want to perish together with America by using nuclear weapons, despite the fact that we have been exclaiming that we will have the Taiwan issue resolved at whatever cost. Only by using non-destructive weapons that can kill many people will we be able to reserve America for ourselves. There has been rapid development of modern biological technology, and new bio-weapons have been invented one after another. Of course, we have not been idle, in the past years we have seized the opportunity to master weapons of this kind. We are capable of achieving our purpose of “cleaning up” America all of a sudden. When Comrade Xiaoping was still with us, the Party Central Committee had the perspicacity to make the right decision not to develop aircraft carrier groups and focus instead on developing lethal weapons that can eliminate mass populations of the enemy country.

…

Of the research done on genetic weapons throughout the world, Israel is the most advanced. Their genetic weapons are designed to target Arabs and protect the Israelis. But even they have not reached the stage of actual deployment. We have cooperated with Israel on some research. Perhaps we can introduce some of the technologies used to protect Israelis and remold these technologies to protect the yellow people. But their technologies are not mature yet, and it is difficult for us to surpass them in a few years. If it has to be five or ten years before some breakthrough can be achieved in genetic weapons, we cannot afford to wait any longer.

RFKjr in the video above: "The races that are most immune are Ashkenazi Jews and Chinese."