The same networks that empower U.S. forces could be their Achilles' heel if troops lose their ability to operate without them. Gen. Martin E. Dempsey, USA, chairman of the Joint Chiefs of Staff, cautioned the audience at Joint Warfighting 2012 in Virginia Beach that the U.S. military needs to be ready for space and cyber to be contested exponentially more than today. "The worst case scenario might be the most likely scenario," he warned. Gen. Dempsey stated that forces must be able to continue when key capabilities are contested. Ubiquitous technologies such as the Global Positioning System probably will be denied at some point. U.S. forces must practice operating in degraded environments frequently. The general added that mission command and adaptive leadership is the best counter to degraded environments.