Researchers are on the edge of technological breakthroughs that could turn today's troops into science-fiction "super soldiers."
Yet the spate of advancements in neurotechnology, biotechnology and drug research may be outrunning the ability of military leaders to keep up with the legal, political and moral issues they raise, according to a recent study.
"One person's Superman is another's Frankenstein's monster," states the report, prepared by experts from California Polytechnic State University and Case Western Reserve University.
Stunning advancements are emerging from the defense industry and the military's own experimental research labs at the Defense Advanced Research Project Agency, the report notes.
For example, some research is focused on how to give troops super-hearing, allowing them to filter out ambient noise and focus on voices for better intelligence or communications gathering.
Other efforts seek to enhance tongues and taste buds to create a sonarlike sensor and identify ways to enhance or replicate in humans the olfactory senses of dogs.
The military is actively seeking ways to use genetic engineering to expand troops' ability to metabolize food and allow them to subsist on grass or other traditionally inedible items that can be found in the field.
Research also is underway on drugs that can help erase troubling memories and reduce post-traumatic stress.
Several DARPA projects involve a contact lens that will allow troops to read messages and get real-time imagery intelligence in the corners of their eyes.
Other initiatives underway:
DARPA is developing brain scans that help monitor an unconscious mind for signs that otherwise might go unnoticed on a conscious level.
The Cognitive Technology Threat Warning System hinges on the belief that "even though a person may not be consciously aware of movement or of unexpected appearance, the brain detects it and triggers a P-300 brainwave," according to DARPA documents.
Using a computer processor to analyze those brain waves, the device can "highlight many events that would otherwise be considered irrelevant but are actually indications of threats or targets, such as a bird flying by or a branch's swaying," the document says.
Such technology would be helpful to tip-of-the-spear grunts, as well as intelligence analysts who spend hours poring over repetitive imagery relayed by drones or other surveillance tools.
Defense contractors are developing combat exoskeletons, or "wearable robots" that will give troops superhuman strength and endurance.
Made of ultralight metal, they use microprocessors to interpret bodily movements and activate hydraulic systems to support a soldier's natural efforts. Current models are large and bulky, but future versions will be far smaller and could be incorporated into clothing or even surgically implanted.
Sleep-related research is using advanced magnetic brain imaging to identify neurological causes of drowsiness. The hope is to find a way to modify brain chemistry to reduce the need for sleep, a power seen elsewhere in nature for example, dolphins shut down only part of their brains for sleep at any one time.
Grounded in reality
Many of these programs are in early development, but the questions they raise are "grounded in reality and not science fiction," the report said.
While robots and unmanned systems are popular among military leaders today, their fundamental limitations the inability to make immediate, nuanced and moral judgments may lead to a shift toward human enhancements.
"Cognitive and physical enhancements aim to create a super-soldier from a biomedical direction, such as with drugs and bionics," the report says. "For battle, we want our soft organic bodies to perform more like machines. Somewhere in between robotics and biomedical research, we might arrive at the perfect future war fighter: one that is part machine and part human."
One key consideration for military leaders is the long-term impact of human enhancements.
"Most war fighters return to society as civilians (our veterans) and would carry back any permanent enhancements and addictions with them," the report says. "Possible solutions … may include a policy to implement only reversible or temporary enhancements in the military as a firewall for broader society."
The report encourages military leaders to consider how human enhancements might affect the relationship between U.S. troops and the local nationals they meet abroad; certain cultures may view such enhancements as immoral.
Scientific enhancements also have the potential to change the way troops and their foes interpret international law.
"If our tolerance for pain [is] dramatically elevated, then what used to count as torture yesterday may no longer be so torturous today, and therefore such behavior may be morally permissible," the report says.
The report cites the example of past controversies about when the military can require troops to be vaccinated without their consent. The military is likely to face those kinds of questions far more frequently in the future.
"Many of these issues are urgent now and need to be actively engaged, ideally in advance of or in parallel with rapidly emerging science and technologies," the report says.