The First Company of the 12th Armored Cavalry Regiment prepared for virtual battle.

At the Combined Arms and Tactical Training Center (CATTC) in Fort Knox, Ky., the troops prepared to enter SIMNET - a virtual war delivered via network links. With the almost Disney-like mimicry typical of SIMNET operations, the warriors were briefed in an actual field command-post, with folding camp-stools, fly swatters, and stenciled jerry cans. The young tankers wore green- and-brown forest camouflage fatigues, black combat boots, and forage caps.

Their command-post canvas tent was pitched inside the giant CATTC barn, right in the midst of silent rows of plastic tank simulators.

The Americans listened to a British officer on NATO exchange, Maj. Rogers, a two-year veteran of Fort Knox's simulator network. The major wore British olive-green, with rolled sleeves and gold-crowned epaulets and a Union Jack at the shoulder. He swiftly explained the tactical situation with deft scribbles on the plastic overlay covering a large topographical map.

Today's engagement would take place in a digital replica of California's Mojave Desert, the bleak, much-mangled terrain that is the heavy-armor stomping grounds of the US Army's National Training Center. Thanks to the Defense Advanced Research Projects Agency (DARPA), the Defense Mapping Agency, and the Army's Topographic Engineering Center, the US military's vast Mojave acreage had been replicated virtually. The virtual Mojave is now available for daily use even in distant Fort Knox (and in an increasing number of other simulation centers around the planet).

The NTC's Mojave was a very harsh terrain, a hell of a place to lose a cow or to throw a tank track, and today it was worse yet, because it was swarming with the Opposing Forces.

The Threat were on their way in overwhelming numbers. Their assault force was