Is there a reliable reference that the US is no longer researching biochemical weapons?
Wikipedia claims: "Both the U.S. bio-weapons ban and the Biological Weapons Convention restricted any work in the area of biological warfare to defensive in nature. In reality, this gives BWC member-states wide latitude to conduct biological weapons research because the BWC contains no provisions for monitoring or enforcement.[74][75] The treaty, essentially, is a gentlemen's agreement amongst members backed by the long-prevailing thought that biological warfare should not be used in battle.[74]"
https://en.wikipedia.org/wiki/United_States_biological_weapo...
Now, try to apply that same reasoning to your allegation without looking silly. Yes, the USG has secretly run certain aspects of a public biowarfare program - and when it came to light they paid. Boom, they couldn't keep it secret and they couldn't escape the consequences (lots of very damaging legal cases and hearings). Finally, do they have an incentive? No - as I said, it makes no sense for them to reduce the cost of yet another world ending weapon. Now you could point to Russia getting caught with massive stockpiles of Anthrax after they claimed to end the program... but their nuclear program's credibility isn't comparable - they've always demonstrated clear signs of insecurity about it. That isn't the case for the USG.