This is a very long article exploring the possibility that SARS-CoV-2 escaped from a lab in Wuhan. The author cites, but does not really discuss, the seminal Nature Med paper that concluded that the virus was not intentionally designed in a lab. He instead emphasizes the interest of some researchers in designing a virus capable of causing a pandemic, not as an agent of bio-terrorism or warfare, but so that we would be prepared to deal with such a virus if/when it emerged naturally. He finds the existence of a level-4 lab in Wuhan too much of a coincidence, and notes that the bat virus with highest sequence homology to SARS-CoV-2 was brought to Wuhan years earlier from a mine shaft, where it was found after several workers shoveling bat guano died from breathing the dust.
While it's a good account of the research being carried out on infectious viruses, and the conflicts over whether the potential benefits in understanding how to treat a new viral design outweigh the risks of just such a lab accident, this is bound to stoke the conspiracy theorists, which I can already see in the first comments. The author's scenario might be described as a hybrid between the standard intentionally designed virus, and the purely accidental theory. The author believes the virus was intentionally designed, just not for nefarious purposes, and since it's proposed to have been designed from a naturally-occurring virus, one of the arguments made in the Nature Med paper--that intentional design would have made use of a different viral backbone--is avoided. However, another argument vs. intentional design--that the spike protein would have been designed differently--would seem to apply to this scenario, as does the furin cleavage site.
The sad thing is that we may very well never know the origins of the virus, as we have not yet found it, or a very close relative that could have easily mutated to SARS-C0V-2, in any animal species. 8472 may jump in here indignantly, but China really hasn't helped by so far delaying if not refusing admission of an investigative team. If China wants to know the origin of the virus, they're sure hiding their intentions from the rest of us.
But in the climate of gonzo laboratory experimentation, at a time when all sorts of tweaked variants and amped-up substitutions were being tested on cell cultures and in the lungs of humanized mice and other experimental animals, isn’t it possible that somebody in Wuhan took the virus that had been isolated from human samples, or the RaTG13 bat virus sequence, or both (or other viruses from that same mine shaft that Shi Zhengli has recently mentioned in passing), and used them to create a challenge disease for vaccine research — a chopped-and-channeled version of RaTG13 or the miners’ virus that included elements that would make it thrive and even rampage in people? And then what if, during an experiment one afternoon, this new, virulent, human-infecting, furin-ready virus got out?