During the cold war I took an Army NBC course on defense against nuclear, chemical and biological attacks. Finding out the cause of any kind of vector that harms the troops is usual I would think- the same principle should apply to civilians too. Then again I enjoy the newer Sherlock Holmes movies , so determining the real source of what could have been low level biological war (or not) would seem to be de rigueur for competent government in my opinion. In other words what was a biologically caused homicide of more than a million people and greater than a half million Americans (isn’t that roughly the total now) should have enough investigation that their isn’t any doubt about the source.
If that is beyond the ability or interest of the U.S. Government, well, that’s just the way it is. A commission should find the source beyond a reasonable doubt, and evaluate the competence of the response as well, with the goal of doing much better in any possible future incident of a similar nature. Alternatively, it may be better to be happy idiots and move on to more cheerful topics knowing that the pandemic could not possibly have been caused by malevolent human agency. If the pandemic was a human trial it might be happier to ignore that chance and wait like cattle for a more serious national biological emergency to wrap the nation blissfully like a warm blanket some day.