Dual-use technologies are technologies that can be applied both for causing death and destruction and for more benign purposes. An xkcd strip last month illustrates the concept beautifully by recycling Isaac Newton's cannonball thought experiment:
In my 2016 book Here Be Dragons: Science, Technology and the Future of Humanity, I point out at some length the troublesome fact that many emerging technologies have this dual-use feature, and that the dangers are in some cases of such a magnitude that they can mean the end of civilization and humanity. How should we react to this fact? I often encounter the attitude that since there are no inherently good or evil technologies but only good or even uses of them, engineers need not worry about ethical concerns when deciding what to develop. In my recent manuscript Vetenskap på gott och ont (in Swedish) I wholeheartedly condemn that attitude, and view it as an attempt to fall back on a simple one-liner in order to grant oneself the luxury of not having to think inconvenient thoughts ("ett simpelt slagord avsett för att slippa tänka obekväma tankar") or take responsibility for the consequences of one's work.
What to do instead? In Here Be Dragons I admit not having any easy answers to that, but suggest that an improved understanding of the landscape of possible future technologies and their consequences for humanity would improve the odds of a happy outcome, and that it might be a good idea to launch some IPCC-like international body with the task of summerizing our (sparse, but improving) knowledge in this field and making that knowledge available to decision makers on all levels (IPCC is short for Intergovernmental Panel on Climate Change). I was pleased to learn, quite recently, that Daniel Bressler at Columbia University and Jeff Alstott at MIT have developed, in some detail, a similar idea for the highly overlapping field of global catastrophic risk. Do have a look at their report The Intergovernmental Panel on Global Catastrophic Risks (IPGCR): A Proposal for a New International Organization.