This new academic paper appeared via a "lurker" and at 108 pgs. is too long to read, so I rely on the Executive Summary:
The United States military is making substantial investments to develop technologies that would
enhance the ability of warfighters to complete their missions safely and effectively. Driven by neuroscience, biotechnology, nanotechnology, robotics, and other emerging technologies, this research includes combating sleep deprivation, improving cognitive performance, increasing strength, reducing muscle fatigue, and other enhancements to the human body and mind.

As with other emerging military technologies, such as robotics and cyber-capabilities, human enhancement technologies challenge existing laws and policy, as well as underlying ethical values. But while the implications of human enhancement generally have been widely discussed, little analysis currently exists for the military context—specifically operational, ethical, and legal implications of enhancing warfighters, such as:

How safe should these human enhancements and new medical treatments be prior to their deployment (considering recent controversies such as mandatory anthrax vaccinations)? Must enhancements be reversible or temporary (considering that most warfighters will return to society as civilians)? Could enhancements count as “biological weapons” under the Biological and Toxin Weapons Convention (considering that the term is not clearly defined)?

This report begins an investigation into these and other issues in order to identify problems that policymakers and society may need to confront.

We start with an analysis of international and domestic law, military policy, bioethics, and risk assessments. Then we offer a new framework for evaluating human enhancement technologies in a military context. As an initial model, we also discuss further considerations—related to character and honor, as well as broader social impacts—that can be integrated later into this evaluative framework.

Given a significant lag time between ethics and technology, it is imperative to start considering the issues before novel technologies fully arrive on the scene and in the theater of war. Consider, for instance, the sudden explosion in number of robots in war and the ensuing confusion and controversies over their use. This report, therefore, is intended to help avoid similar ethical, legal, and policy surprises, as well as technology misuses that affect national
reputations and real lives.