Engadget reports today a story from the Register that DARPA is going to move forward with a plan to electronically tag each soldier. The ultimate plan is to be able to locate each soldier in case of trouble and to use this tag to allow access to equipment. As with all security plans it is not without flaws.
Any system that uses radio waves can be tracked, even if it is not decoded it will have to emit some signal to be of any use. I know that our military has electronic monitoring capabilities and it would be no stretch to imagine a divce that would listen for the tag and warn the enemy of approaching doom.