To add to the irony, technology and war had found new use for vacant space. World War II redirected much of the western economy toward defense industries and military development. The large-scale testing of planes, tanks, guns, and bombs required wide open spaces -- unoccupied land that would be easy to acquire and suitable for simulated attack. The deserts provided ideal locations undeveloped enough so that little in the way of improvement would be lost, isolated so that secrecy could be maintained. Since undeveloped deserts were already by popular consensus vacant and useless, bombing could hardly hurt them. In Arizona's Yuma Proving Ground and Luke Air Force Base, in California's China Lake Naval Weapons Center, Randsburgh Wash Test Range, Camp Irwin Edwards Air Force Base, Twenty-nine Palms Marine Corps Base, and Chocolate Mountains Aerial Gunnery Range, in Nevada's Tonopa Test Range, Nellis Air Force Range, and Atomic Energy Commission Nuclear Testing Site, in New Mexico's White Sands Missile Range and Fort Bliss Military Reservation, and in Utah's Dugway Proving Groundsand Wendover Bombing and Gunnery Range, defense projects made it clear that an "endless sea of nothingness" had its uses.

When the scientists at Los Alamos needed a place to test the first atomic bomb, the New Mexico desert met the job requirements. The place called Trinity on the old Jornada del Muerto connecting El Paso to Santa Fe was, as Lansing Lamont wrote, "the perfect place to test the bomb." It was "isolated," "flat," "so uninhabitable that the nearest signs of civilization were a pair of abandoned coal mining towns, Troy and Carthage.... If disaster occurred, few besides the scientists at Trinity would be victims." Even Joseph Wood Krutch commented on the fit between place and purpose: "There must be very few places in the United States so suitable for such an experiment; few, that is to say, either so remote or so devoid of anything to be destroyed." It was almost providential -- the way in which aridity had reserved certain regions from settlement, and therefore left them suitable for bombing.

To the north and west of Trinity, twentieth-century enterprise revealed other ways of making use of deserts. When mining proved a changeable and unreliable base for prosperity, the state legislature of Nevada entertained other routes to revenue. In 1931, the legislators added wonderfully to the resources of Nevada by legalizing gambling. Here was a sensible and practical way of capitalizing on uncertainty; gambling followed symmetrically in the traditions of Americans in deserts. Overland emigrants had been gamblers, staking their lives on the uncertainties and risks of desert traveling. Prospectors had been gamblers, staking their resources and sometimes their lives on the chances and hazards of desert treasure-hunting. Irrigationists were gamblers, staking their enterprise on the unlimited extendability of desert water sources and on the changing currents of national politics. Tourist and town promoters were and are gamblers, staking their businesses on the uncertain capacity of the deserts to sustain heavy settlement and use. The eager crowds who flocked to the tables and slot machines of Las Vegas were well within the tradition of travelers in, as John W. Audubon described it in 1849, "a doubtful country."'

When gamblers fail to get what they want, it is second nature for them to claim betrayal. Describing contemporary Americans, Richard Barnet has analyzed the response to resource scarcity: "The new mood," he said, "is no conventional pessimism, but rather a loss of faith rooted in a sense of betrayal." For four centuries nature in the New World offered Euro-Americans promises of abundance. One region reneged on that promise from the beginning. Facing the uncooperative behavior of nature in the desert, nineteenth-century Anglo-Americans experienced at least briefly a version of that "loss of faith rooted in a sense of betrayal." William Ellsworth Smythe and his heirs have done their best to shore up the faith, but the doubts aroused by aridity do not go away. This is the stage in the game in which the gamblers could profitably refrain from further bets, and reconsider their strategy.