The US Army is building a second version of Earth on computer to help it prepare for conflicts around the world. The detailed simulation will be drawn from a real-world terrain database and will be drawn to the same scale as the original.
The software Earth is being created for the US Army by gaming company There, which is currently working on a virtual world for gamers.
The first version of the virtual planet should be finished by September.
Mr Gehorsam said the world being created will not be a game but instead will be a "massively multi-user persistent environment" that will model real world physics as closely as possible.
The emphasis in the artificial Earth will be on human interaction rather than conflicts involving lots of military hardware.
He said combat will be a part of the game but it is also intended to let the Army simulate intelligence work as well as patrols, planning and working with indigenous populations.