The radioactivity never did rise much beyond a mildly hazardous level, and that was only transient, during the second week of the war--the week called the Death of Cities. The small shards of sanity retained by the high commands on both sides dictated avoiding weapons with a built-in backfire: no cobalt bombs were dropped, no territories permanently poisoned. Generals still remembered that unoccupied territory, no matter how devastated, is still unconquered territory. But no such considerations stood in the way of biological warfare. It was controllable: you never released against the enemy any disease you didn't yourself know how to control. There would be some slips, of course, but the margin for error-- There were some slips. But for the most part, biological warfare worked fine. The great fevers washed like tides around and around the globe, one after another. In such cities as had escaped the bombings, the rumble of truck convoys carrying the puffed heaped corpses to the mass graves became the only sound except for sporadic small-arms fire; and then that too ceased, and the trucks stood rusting in rows. Nor were human beings the sole victims. Cattle fevers were sent out. Wheat rusts, rice molds, corn blights, hog choleras, poultry enteritises fountained into the indifferent air from the hidden laboratories, or were loosed far aloft, in the jet-stream, by rocketing fleets. Gelatin capsules pullulating with gill-rots fell like hail into the great fishing grounds of Newfoundland, Oregon, Japan, Sweden, Portugal. Hundreds of species of animals were drafted as secondary hosts for human diseases, were injected and released to carry the blessings of the laboratories to their mates and litters. It was discovered that minute amounts of the tetracycline series of antibiotics, which had long been used as feed supplements to bring farm animals to full market weight early, could also be used to raise the most whopping Anopheles and Aëdes mosquitoes anybody ever saw, capable of flying long distances against the wind and of carrying a peculiarly interesting new strains of the malarial parasite and the yellow fever virus.... By the time it had ended, everyone who remained alive was a mile under ground. For good. * * * * * "I still fail to understand why," Hamelin said, "if, as you claim, you have methods of re-educating soldiers for surface life, you can't do so for civilians as well. Or instead." The under-secretary, a tall, spare man, bald on top, and with a heavily creased forehead, spoke with the odd neutral accent--untinged by regionalism--of the trained diplomat, despite the fact that there had been no such thing as a foreign service for nearly half a century. "We're going to try to explain that to you," Carson said. "But we thought that, first of all, we'd try to explain once more why we think it would be bad policy--as well as physically out of the question.