http://www.thenewamerican.com/tech/computers/item/11286-us-military-seeking-implantable-microchips-in-soldiers
The U.S. government is developing implantable sensor microchips for use in American troops, supposedly to monitor their health on the battlefield, the Defense Advanced Research Projects Agency (DARPA) announced earlier this year seeking proposals. But critics of the scheme are speaking out, warning that the new technology could just be a prelude to expanding the use of related devices among the general population — with dangerous implications for freedom and privacy.

According to news reports about the development, DARPA believes that being able to instantly receive updates about any potential medical problems among soldiers would give the U.S. armed forces an advantage over adversaries. Calling the implants "a truly disruptive innovation," the agency said the nanotechnology could revolutionize war — especially because most medical evacuations are a result of illness or disease rather than injuries sustained in battle.