My nitpick is the vague and spooky description of Paul Berg's research. The surrounding tone is great, but this little bit ends up sounding bad.

Current:

Paul Berg (1926-), who carried out part of an experiment (like what?) which would, if completed, have created a potentially carcinogenic (vague) strain of a common gut bacteria (just say E. coli) which could have spread to human beings (Say what relevant people at the time thought, "could have" implies false danger). Due to the concerns of other scientists, he put the final part of the experiment on hold, and called for more attention to the risks of such research as well as a temporary moratorium.

Preferred:

Paul Berg (1926-), who in 1972 had already carried out the preparations for creating a strain of E. coli that contained the genome for a human-infectious virus (SV40) with tentative links to cancer. Robert Pollack (1920-) heard news of this experiment and helped convince Berg to halt it - both were concerned about the danger that this new strain would spread to humans in the lab and become a pathogen. Berg then became a major voice calling for more attention to the risks of such research as well as a temporary moratorium.