Nathan Mhyrvold is the former Chief Technology Officer for Microsoft and founder of Intellectual Ventures. To put it mildly, he is a fairly smart guy. Mr. Mhyrvold decided to publish a ‘little’ research paper titled Strategic Terrorism A Call to Action.

Click to access Strategic-Terrorism-Myhrvold-7-3-2013.pdf

This paper warns that the potential for a massive human induced loss of life several million to potential extinction is much easier than people tend to think. It is a long read, but I think Mr. Mhyrvold lays out his argument well.

Technology contains no inherent moral directive—it empowers people, whatever their intent, good or evil. This fact, of course, has always been true: when bronze implements supplanted those made of stone, the ancient world got swords and battle-axes as well as scythes and awls. every technology has violent applications because that is one of the first things we humans ask of our tools.
The novelty of our present situation is that modern technology can provide small groups of people with much greater lethality than ever before. We now have to worry that private parties might gain access to weapons that are as destructive as—or possibly even more destructive than—those held by any nation-state. a handful of people, perhaps even a single individual, now have the ability to kill millions or even billions. indeed, it is perfectly feasible, from a technological standpoint, to kill every man, woman, and child on earth. The gravity of the situation is so extreme that getting the concept across without seeming silly or alarmist is challenging. Just thinking about the subject with any degree of seriousness numbs the mind.
Worries about the future of the human race are hardly novel. indeed, the notion that terrorists or others might use weapons of mass destruction is so commonplace as to be almost passé. spy novels, movies, and television dramas explore this plot frequently. We have become desensitized to this entire genre, in part because James Bond always manages to save the world in the end.