How accurate is accurate?

...No one knows just how hard modern missile silos are, and the military estimates are naturally classified, but the professional literature on these matters cites figures of 2000-4000 psi...

...CEP means "circular error probable" and refers to the radius, generally given in nautical miles, of a circle around a target within which half the missiles aimed at it will land...

...American missile tests are mostly conducted from East to West across the Pacific...

...German air defenses forced the bombers to fly too high for truly accurate bombing, and the British, at least, decided early in the war to fly only at night...

...They wanted to win wars, not murder half the globe...

...THOMAS POWERSilding it...

...As soon as military planners on both sides began to get more accurate weapons, they aimed them at different targets, generally of a military nature...

...The Norden bombsight was popularly believed to allow "surgical strikes" and "pinpoint bombing" but one man's pinpoint, as the Strategic Bombing Survey revealed after the war, was often another man's cow pasture...

...In this regard battle and boxing have much in common...

...The American military-and very likely the Russians as well-were unhappy with this approach...

...The first is whether any missile can have a reliable CEP on the order of 0.1 to 0.3 nm...

...If you can destroy enemy weapons, you must...

...daylight raid on the German ball-bearing plants in Schwein-furt in August, 1943, was typical...

...A further danger posed by a counter-force threat is the fact that the best defense against it would be a computer-controlled launch-on-warning system...

...This fact is now the driving force behind American nuclear weapons policy, the thing which explains what we are building and why we are building it...

...This was a failure too...

...Air Force had little confidence in its ability to hit things...

...The blow must land on the exact spot where a soldier or a tank or a submarine is...

...A missile with a CEP of 0.25 nm...

...The cautionary critics are right about that...

...They made them very hard indeed...

...But weapons and the men who wield them are somewhere, and it is there a blow must be landed to be effective...

...THOMAS POWERS...

...In modern war the emphasis has been on volume of fire, not target practice, as a means of hitting an enemy...

...In the course of the raid about 60 U.S...

...The cautionary critics argue that variations in bias make CEPs unreliable...

...In the popular mind The Bomb is a weapon of Armageddon, a tool of apocalypse, an instrument of total destruction, a means to obliterate an enemy...

...A major U.S...

...Missiles were quicker, re-entering the atmosphere at better than 10,000 miles an hour, but the early warheads were so bulky, and the whole vehicle so technically crude, that the CEP of the first American ICBM-the Atlas -was "several miles," probably about five...

...It is highly particular...

...But talk of first strikes has an unreal quality to it...

...Cities we could hit, but cities weren't the enemy...

...Impact photos showed that only one in four had actually dropped bombs within five miles of the target...

...But this shifts the whole discussion from a technical point to a debating point-from the question of accuracy to a question of Russian intent to prepare for a first-strike...

...In the literature this is referred to as the "use it or lose it syndrome...

...Pain we could cause, but pain doesn't win wars...

...War is much the same...

...The first strike argument is in fact little more than a useful theoretical tool for comparing the characteristics of weapons...

...With a handful of fanatic exceptions, not even the military believe the Russians are craftily preparing a surprise blow...

...Their deaths did not shorten the war by a day...

...Then, truly, the human race would have surrendered its fate to Fate...

...That is also the factor which has generated the most argument during the last few years...

...The argument over counter-force accuracy centers on three points...

...What ruling group, the cautionary critics ask, would risk the fate of its regime and country on something which has to work perfectly the first time...

...Hundreds of thousands of civilians were killed by the three million tons of Allied bombs dropped on Germany...

...From time to time, since 1945, the defense community in Washington has alarmed itself with claims the Russians were close to achieving a genuine first-strike capability...

...The 8th Air Force and the British Bomber Command referred to this sort of thing as "strategic bombing," which they hoped would shorten the war...

...Flying at night at high altitudes, the British switched targets to something they felt they could hit-cities...

...The second point of contention, pressed by the cautionary critics, concerns the question of bias-the known tendency of any missile to miss the target...

...Further improvements in accuracy can be expected from terminal-guidance-that is, homing techniques -and from satellite-navigational systems...

...The target was simply people, on the theory that killing enough of them would crack civilian morale and perhaps spark the sort of popular revolution which ended the First World War...

...It is our genius as a species to be able to find a way to do anything we can imagine...

...But it is important to recognize that cities did not become targets because that's where "the enemy" is, but simply because they are big enough to find at night and to hit...

...Of several minds: Thomas Powers HOW ACCURATE'S ACCURATE A MISS IS AS GOOD AS A MILE ONE OF THE better-kept secrets of World War II was the fact that bombers had a hard time hitting anything-that is, anything in particular...

...But in the event of war it would be equally crazy to let alone what immediately threatens-weapons and the systems which control them...

...Awfully few bombs inside the circle," the official said...

...Ordinary citizens in crowded cities, men and women like you and me, the victims- not the planners-of war...

...At any rate, the war ended shortly thereafter...

...The Air Force, which periodically fires Min-uteman III missiles from Vandenberg Air Force Base in California to Kwajalein Lagoon in the Southern Pacific, claims we are already within that range and that the MX will do even better...

...might have a bias of 0.1 nm...

...A coordinated mass launch involves so many unknowns and imponderables that Jimmy Carter's Secretary of Defense, Harold Brown, once referred to it as "a cosmic throw of the dice...

...where the Soviets are concerned, and that the advent of counter-force weapons will destabilize the balance of terror by pushing both sides to fire first in a crisis, rather than run the risk of losing its weapons on the ground...

...It was just a place so big you couldn't miss it, and so crowded with people the result was bound to be on an unprecedented scale of horror...

...Five miles away won't do...

...There is indeed grave risk in using ballistic missiles," he concluded, "but that risk is not uncertainty of accuracy...

...The new approach, never officially acknowledged, called for destroying the industrial suburbs where workers lived...

...Nevertheless, the goal has always remained accuracy-a particular blow on a particular spot-and the recent development of precision-guided munitions threatens to transform war on the battlefield...

...Accurate missiles prepare the ground for nuclear war-extended fighting for purely military objectives, a clash of weapons...

...It is accuracy which determines the efficacy of violence in war...

...a regime would have to be crazy to contemplate such a thing...

...On two occasions-Hamburg in July, 1943, and Dresden in February, 1945 - firestorms were created which turned huge areas of the target cities, into smoking wastelands, killing scores of thousands of people, but the effect on German war production was negligible...

...This change has been a long time in coming...

...The 8th Air Force later concluded there were 88 "direct hits"-that is, bombs which landed in the general plant area- and 55 actual strikes on factory buildings...

...The day of the bombing Truman described the city as a military target, but it was nothing of the sort, as he doubtless knew...

...bombers with their eight-man crews were shot down- roughly one for every bomb that landed on a factory building...

...Hardness to that degree means that a missile silo could only be destroyed by a direct hit-a warhead detonating sufficiently close by to put the silo inside the fireball (about a mile in diameter for a 1 megaton burst in the air), or inside the crater (about half a mile in diameter for a 1 megaton burst on the ground...

...They can destroy anything on or reasonably near the surface of the earth, so long as we know where it is...

...No one doubts such a war would wreck the world...

...So the Americans, and later the Russians, put their missiles underground in silos, and then hardened the silos with steel and concrete...

...Another Bomber Command study, conducted earlier in the war, examined the actual results of bombs dropped by pilots-about half of those taking part in the raid-who claimed to have hit the target...

...But who is "the enemy...

...This suggests that a missile intended to destroy a hardened missile silo would require a CEP of about 0.4 nm...

...An ordinary brick house in the Georgian style, say, would be largely destroyed by an overpressure of 5 pounds per square inch, or 5 psi...

...An attack on Russia would require firing over the North Pole...

...With the advent of thermonuclear weapons this was close enough to destroy pretty much anything fixed on the ground, but of course the bombers took so long to arrive there was no chance of finding the enemy's bombers still on the ground...

...The law of averages is expected to do what aiming cannot...

...But missile accuracy makes such a war possible and indeed forces the hand of military planners...

...Early in 1945 a huge 1000-plane raid generated a firestorm in Tokyo which leveled hundreds of acres of housing and killed more people than either Hiroshima or Nagasaki...

...Five miles was close enough...

...But even putting it that way is a kind of euphemism...

...The trouble with this argument is that ICBMs have been tested over a long period of time, and results show whatever they show...

...One Air Force officer told me a year ago that he and his colleagues routinely cite CEPs in terms of feet, and another said the second generation MX, already being designed, will have a CEP of about 90 feet...

...Bias is a fixed quantity, a number like CEP, which represents the distance between the center of a cluster of impact points and the intended target, as established by actual test results...

...for a 1 megaton warhead...

...Military and technical men who have studied the results generally insist the missiles can really attain the accuracies claimed for them...

...In the final stages of the war against Japan the Americans, too, finally abandoned the illusion of "pinpoint" bombing and adopted the British approach...

...The truth of the matter is that missiles are accurate enough to serve as counter-force weapons...

...The first bomb was dropped on Hiroshima because a city was something we could hit...

...The long history of technical improvement of inertial guidance systems has reduced CEPs from miles to fractions of miles to hundreds of feet...

...The argument, highly technical in its extended form, centers on a claim by a group of defense analysts in Washington that the Soviets now have missiles sufficiently accurate to serve as counter-force weapons-that is, to pose a threat to our weapons of fixed location (Minuteman silos, bombers on airfields, and nuclear submarines in port...

...You'd better change that to a five-mile circle before it goes in...

...Down the street won't do...

...Freeman J. Dyson, the British-born physicist now at Princeton, worked on operational research during the war, and was often appalled at the poor results when he drew up bomb plots after the raids...

...The plan worked...

...The ball-bearing plant, while damaged, was soon back up to normal production...

...In the late 1940s and early 1950s the U.S...

...It is said that the towns in Germany are only two kilotons apart...

...It is the technical point, the question of accuracy, which really matters...

...There are many other factors which must be weighted in estimating the "probability of kill" (the PK) of a given warhead against a given target, but the most important of them by far is accuracy...

...The most important military targets, of course, are weapons, and the most dangerous weapons are nuclear weapons...

...Another result was a change in strategy, from "pinpoint" bombing of im-portant factories, railroad marshaling yards, dry docks and so on, to "area bombing...

...This inability to hit things accurately with bombs had several results...

...means half the missiles will land within 5 miles of the target...

...Charles Draper, the Einstein of missile guidance who runs the laboratory named after him at MIT, recently published a letter in the New York Times in which he admitted the bias problem but said the point was whether it was "greater than the lethal radius of the warhead . . ." Back in the late 1940s, when missile-designers were still thinking in terms of 5 nm...

...Weapons make an opponent formidable, and it is weapons which must be destroyed...

...Boxers bob and weave and jab but they do not often land a solid punch...

...It takes tons of munitions to produce a single enemy casualty in this way, but production is what modern industrial states are best at...

...The B-47 bomber was thought to be doing fine if it dropped its bombs within 2500 feet of the target...

...Even one or two, properly placed, can be enough to do the job...

...But the point of contention most difficult to settle involves the problems in coordinating the launch of many hundreds of missiles so that their warheads would land pretty much simultaneously on their targets, a sine qua non for a successful first-strike...

...Another problem is "fratricide"-the danger that warheads exploding on target will destroy others as they arrive nearby...

...The rest of the bombs landed somewhere, too, of course, and killed about 300 German civilians, including 26 children, and another 100 slave laborers from Poland and France...

...It did not...

...The current episode of fear has not yet ended...

...His most important weapons, therefore, could not be destroyed...

...A second group of defense analysts claims the first is crying "Wolf...

...The Soviet counter-force threat is cited as a principal argument for building the MX or some other, perhaps mobile, land-based system of un-fixed location, and for building counter-force (i.e., accurate) missiles of our own...

...The "bomber gap" of the early-50s and the "missile gap'' of a few years later proved chimerical...

...This might "save" the threatened weapons (by using them) but it would make the world hostage to computer-error, which while it might be improbable, could never be impossible...

...The earliest missiles stood up in the open and could be knocked over by a firm shock wave...

...The technology which raised volume of fire to nightmarish levels, now allows us to really hit things...

...A bias can have many causes- idiosyncracies of the hardware, gravitational anomalies along its flight path, severe weather conditions in the area of re-entry...

...In his memoirs, Disturbing the Universe, Dyson describes the reaction of one Bomber Command official to a preliminary bomb plot recording the results of a raid on Frankfurt...

...No man has had more to do with making American missiles accurate, and he claims bias is not greater than the lethal radius...

...The machine gun, the artillery barrage, and carpet bombing are all ways of directing many lethal missiles to the general area where the enemy is...

...With nuclear weapons, in spite of their great power, the importance of accuracy is equally acute...

...Bombs were dropped all over Europe, but rarely on target...

...For one thing, many of the missiles would have to pass through the same "window" at the apogee of their trajectories in order to land on contiguous targets...

...Ever since, cities have been high on the target lists and their dwellers have lived unhappily with a kind of vision of the way the world will end...

...CEPs, Draper predicted we would eventually get to 0.1 nm...

...A CEP of 5 nm...

...A total of 1122 high explosive bombs weighing 395 tons were dropped by 376 bombers...

...One was a high level of gratuitous killing and destruction...

...The significance of accuracy is not that it clears the way for a first strike...

...According to the defense consultant Richard Garwin, an authority in these matters, every missile has a bias, and it has never been predicted in advance...