WITH millions of land mines thought to be hidden in Bosnia-Herzegovina's snow-covered fields and forests, knowing where to tread may mean the difference between life and death for American peacekeeping troops.
To ensure they don't stray in the rugged and unfamiliar terrain, US units will be carrying hand-held devices that can pinpoint their locations to within 15 meters (49 feet) by triangulating with a network of 24 satellites orbiting the earth.
The Global Positioning System (GPS) is among an array of advanced communications tools, remote sensors, and other technologies that will be used by the 20,000 US soldiers of the NATO contingent deploying to enforce the peace accord between Bosnia's Serbs, Muslims, and Croats.
These systems are on the cutting edge of a "revolution in military affairs," say military analysts. Such fusions of technological innovation with new tactics and military structures have marked critical shifts in the use of military power throughout history.
High-Tech Gadgets Put to Test in Bosnia
Just as the invention of firearms, tanks, and aircraft wrought fundamental changes in the conduct of war, the US military has been working to harness computers, satellite systems, and other technologies to dominate the "information battlefield."
Critics inside and outside the military are warning against an over-reliance on high technology, saying the Pentagon is short-changing basic requirements such as tent pegs and boots. But advocates insist that to prevail in 21st century warfare, the United States must pursue advances in weaponry and military technologies.
Bosnia should provide the next test of some of these systems.
The 1991 Persian Gulf war was the first conflict in which the new generation of technologies and weaponry was employed. The experience produced some refinements, especially the dissemination of information gathered by satellites, military officials say.
"We have focused efforts in all of the services on better exploitation of the resources that we invested in space and space systems," says Maj. Gen. David Vesely of the US Space Command.
Improvements in the use of satellites and other surveillance technologies will help US forces in Bosnia in their main task of policing a 2.5-mile-wide "zone of separation" between the forces of the Muslim-Croat federation and the Bosnian Serbs' Republika Srpska.
Among other devices, US forces will deploy lines of remote sensors to thwart infiltration of areas too rugged to patrol on foot or too inhospitable to maintain permanent bases. "If anyone crossed ... the sensors would tell us they are there and NATO forces could go out and take a look," explains Lt. Gen. Howell Estes, director of operations for the Joint Chiefs of Staff.
Apache and Kiowa helicopters that will overfly the separation zones will have heat-detecting sensors and cameras capable of monitoring human movements up to a mile away. The Apaches will be equipped with a system that can transmit video pictures to ground commanders within 90 seconds.
Using new computer-simulation programs and digitized maps, the helicopter pilots can fly practice runs over a particular route before doing it for real. They will have improved night-vision equipment.
Aiding the monitoring effort will be U-2 spy planes and RC-135 Joint Rivet surveillance aircraft that can take photographs and intercept radio transmissions. Overflights will also be made by unmanned surveillance aircraft, known as Predators, which can linger for days over a piece of terrain while transmitting video pictures.
The most advanced airborne system will be the Joint Surveillance and Target Attack Radar System, or JSTARS. This aircraft, two of which are to be used over Bosnia, can track large-scale movements of troops and armor. It is so versatile it can differentiate between tanks and armored personnel carriers. One of those being sent to Bosnia is a new, more powerful version of the JSTARS that was used for the first time in the Gulf war.
Eyes in the sky
Far above the battlefield, a constellation of military and commercial satellites is being employed to provide information on weather conditions to ground troops.
The aircraft flying troops and equipment into Tuzla, where the US headquarters is based, are equipped with the Multiple Source Tactical System, an instrument that displays data from satellites on flight routes, ground threats, and weather conditions.
The importance of getting satellite information to pilots and troops on the ground was one of the main lessons the US military learned from the Gulf war, experts say. Because of lingering cold-war-era secrecy, American intelligence agencies that control the satellites were unwilling or too slow during the conflict to give military commanders pictures of Iraqi positions.
American forces in Bosnia, however, will benefit from post-Gulf war efforts aimed at getting satellite intelligence as quickly as possible to ground troops eager to learn of possible threats lurking in the next valley.
"At the time of the Gulf war, a lot of the satellite imagery was classified at a very high level," explains Steve Aftergood, a military analyst with the Federation of American Scientists.
"Most of that imagery has now been downgraded to ... a pretty low level," he adds. "That means it flows a lot more smoothly and gets to where it needs to go."