The atom bomb the United States dropped on Hiroshima in August 1945 had a yield of roughly 18 kilotons, instantly killed 100,000 Japanese citizens and flattened large swathes of the city. Its devastating effects would be felt for decades afterwards. Indeed, that death toll may very well have doubled by the end of the same year through burns and radiation sickness. The numbers for the city of Nagasaki, bombed three days later, are equally mind-boggling.
It was President Harry S Truman who signed the order to use nuclear weapons and although the motives for such an act are ultimately unfathomable, they have long been believed to be two-fold: firstly, to induce the Japanese armed forces to surrender immediately rather than prolong the bloody island-hopping war then taking place in the Pacific; secondly, to instil some caution into the leadership of the Soviet Union, which had driven the Nazis pell-mell across Eastern Europe in 1945 and looked eager to set up permanent residence in Germany and along the Polish Corridor.
Whether or not these aims were achieved, Truman's use of atom bombs had at least one dramatic effect: it changed the imagination of warfare itself, from a practice of the possible to a horrifying contest of the theoretical. Previously, nations only had to consider two outcomes of war - victory or defeat. The theoretical aspect of nuclear war introduced a grotesque third, in which victory and defeat were indistinguishable - and irrelevant in any case, since nobody would be around to experience it. As L Douglas Keeney reminds us in 15 Minutes, his tense, utterly absorbing book, it was in the nuclear era that the phrase "mutually assured destruction" entered the lexicon.
As 15 Minutes demonstrates with relentless precision, the concept of nuclear war evolved in step with the means of nuclear war. When Hiroshima and Nagasaki were rased, there was only one nuclear power in the world, but things would not stay that way. In the immediate post-war years, the Soviets scooped up as many former German scientists as they could reasonably find and bankrolled German spies, in a concerted effort to end the American monopoly on atomic weapons. That monopoly ended in 1949 when the Russians test-detonated a bomb of their own and the Cold War started in earnest.
Keeney's book is not a history of that strangest of all wars, nor is it a history of aviation developments, although aircraft technology necessarily changed radically in connection with atomic escalation, since the progress of nuclear weapons was always linked to the progress of the aircraft that would carry them. Rather, what Keeney has done - through copious, often groundbreaking research and in stark, often strident tones - is vividly sketch out a nightmare that worsened for almost five decades.
The central figure in Keeney's depiction of that nightmare is General Curtis LeMay, who found Strategic Air Command (SAC) a small, underfunded, largely incompetent branch of the US Air Force and left it a massive, well-financed semiautonomous entity, boasting hundreds of bomber jets and many thousands of bombs, each one much more powerful than those that were used in 1945. LeMay had been an expert pilot himself during the Second World War; he had masterminded bombing missions over both Germany and Japan, and he was an aggressive believer in American military might. In Keeney's account, LeMay is a bomber jet in human form, entirely focused on delivering harm to the enemy, regardless of the cost to his own men. As Keeney recounts: "LeMay would later remark that if he were to meet one of his crewmen lost on a mission, he felt certain that he would be able to say to him, 'You were properly expended, Gus. It was part of the price.'"
As Keeney points out, LeMay was the perfect man for a job in which bomber aircraft were considered essential, as the concept of nuclear war evolved from a scenario in which enemy cities were destroyed to one in which the enemy's entire civilisation was laid to waste. The bombs themselves continued to improve, based on a new core design that drastically increased yield while at the same time significantly reducing bulk.
"The idea," Keeney writes, "was to suspend a ball of fissionable material inside a shell of uranium surrounded by the curved lens of high explosives so that on detonation the shell would be slammed into the core and thus more powerfully compress the capsule." The hardware delivering these payloads was equally mutable: "Atomic bombs were upgraded, modified, retrofitted, field modified, and, in some cases, had interchangeable parts with other bombs. Taken together, it took an expert with a slide rule and a furrowed brow to know what casing contained what core with what parachute and what sets of fuses for what yield."
Since this arsenal - and its Soviet equivalent - was designed to rain crippling destruction on the enemy's territory, the key to retaliation was to make sure you had plenty of missiles that weren't located in your territory: LeMay spearheaded the use of tanker aircraft for refuelling bombers in flight, while submarines armed with ballistic missiles prowled the world's oceans far from their homelands.
It's a mark both of the times he chronicles and his skill in doing so, that so much of Keeney's book will strike his youngest readers as the stuff of bad science fiction - or dark comedy. Every chapter contains stories of faulty wiring, clueless crews, technical and mechanical ineptitude and lost bombs.
After 1952, virtually all United States combat aircraft were fitted to carry atom bombs - SAC was joined by the Air Force and the Navy, each with its own procedures, protocols and war plans, none of which was co-ordinated with any of the others. In 1966, a B-52 bomber carrying four MK-28 hydrogen bombs crashed near the village of Palomares, Spain, scattering wreckage everywhere - except for one of the bombs, which couldn't be found.
The Soviets immediately sent trawlers, and the US Air Force hurriedly scrambled their own recovery teams. Once word got out, angry crowds surrounded the American embassy in Madrid, and the search for the missing bomb went on for three months, until finally "on April 7, 1966, the bomb was pulled out of the water and laid on the deck of the USS Petrel. The navy pulled back the tarpaulin, 'The world's eyes may see that the bomb has been found,' said Admiral Wetherby Hill. Cameras snapped the first pictures ever taken of a thermonuclear bomb".
Keeney includes a recently declassified memorandum of a meeting of senior Defense Department and State Department officials, including President Kennedy's Secretary of Defense Robert McNamara, in which the latter makes reference to the crashes of two US aircraft, one in North Carolina and one in Texas, where "by the slightest margin of chance, literally the failure of two wires to cross, a nuclear explosion was averted." The author goes on to point out that although the date of that memorandum was 1963, no document has yet been declassified that makes any mention of a crash like that one in Texas - so did McNamara misspeak, misremember, and if not, how many other terrifying secret close calls did the US and the Soviets have?
When the Soviet Union fell in 1991, the SAC fell with it, disbanded and reabsorbed into the US armed services, and the era of crazed, insomniac bomber pilots carrying cargoes capable of wiping out all of humanity came to an end. Keeney is frank throughout his book when dealing with LeMay's well-known belligerence, but he is equally frank in giving the man credit: SAC's taut discipline and belief in the "deterrent" threat of atomic annihilation played a key role in preventing the Cold War from turning hot. Considering the unprecedented parameters of his job, Keeney contends, he was "an exemplary general". Looking back from the vantage point of our own age, an assessment as downright strange as "exemplary general" may be the Cold War's final irony.
Steve Donoghue is managing editor of Open Letters Monthly.