|Nike Zeus B|
Nike Zeus B test launch at White Sands
|Place of origin||United States|
|Mass||24,200 lb (11,000 kg) total|
|Length||50 feet 2 inches (15.29 m) total|
|Diameter||36 inches (910 mm)|
|Engine||450,000 lbf (2,000,000 N) booster|
|75 nmi (139 km; 86 mi)|
|Flight ceiling||over 150 nmi (280 km; 170 mi)|
|Speed||greater than Mach 4|
Nike Zeus was an
The nature of the strategic threat changed dramatically during the period that Zeus was being developed. Originally expected to face only a few dozen ICBMs, a nationwide defense was feasible, although expensive. In 1957, growing fears of a Soviet sneak attack led it to be repositioned as a way to protect
The system was the topic of intense inter-service rivalry throughout its lifetime. When the ABM role was given to the Army in 1958, the
The decision whether to proceed with Zeus eventually fell to President
The first known serious study on attacking
However, these results also noted that the system might be able to work against longer-ranged missiles. Although these traveled at very high speeds, their higher altitude trajectories made detection simpler, and the longer flight times provided more time to prepare. Both projects were allowed to continue as research efforts, and were transferred to the US Air Force when that force
The Army contacted the
The first section of the Bell study was returned to the Army Ordnance department at the
Considering the ICBM problem, the study went on to suggest that the system would have to be effective between 95 and 100% of the time in order to be worthwhile. They considered attacks against the RV while the missile was in the midcourse, just as it reached the highest point in its trajectory and was traveling at its slowest speed. Practical limitations eliminated this possibility, as it required the ABM to be launched at about the same time as the ICBM in order to meet in the middle, and they could not imagine a way to arrange this. Working at much shorter ranges, during the terminal phase, seemed the only possible solution.
Bell returned a further study, delivered on 4 January 1956, that demonstrated the need to intercept the incoming warheads at 100-mile (160 km) altitude, and suggested that this was within the abilities of an upgraded version of the Nike B missile. Given a terminal speed up to 5 miles per second (18,000 miles per hour (29,000 km/h)), combined with the time it would take an interceptor missile to climb to the RV's altitude, the system required that the RV be initially detected at about 1,000 miles (1,600 km) range. Due to the RV's relatively small size and limited radar signature, this would demand extremely powerful radars.
To ensure the destruction of the RV, or at least render the warhead within it unusable, the
The interceptor would lose maneuverability as it climbed out of the atmosphere and its aerodynamic surfaces became less effective, so it would have to be directed onto the target as rapidly as possible, leaving only minor fine tuning later in the engagement. This required that accurate
After running 50,000 simulated intercepts on
The Army and Air Force had been involved in interservice fighting over missile systems since they split in 1947. The Army considered
By the mid-1950s some of these projects were simply tit-for-tat efforts. When the Army's Hercules began deployment, the Air Force complained that it was inferior to their Bomarc and that the Army was "unfit to guard the nation". When the Army started its
In a 26 November 1956 memorandum, US Secretary of Defense
The result was another round of fighting between the two forces. Jupiter had been designed to be a highly accurate weapon able to attack Soviet military bases in Europe, as compared to Thor, which was intended to attack Soviet cities and had accuracy on the order of several miles. Losing Jupiter, the Army was eliminated from any offensive strategic role. In return, the Air Force complained that Zeus was too long-ranged and the ABM effort should center on Wizard. But the Jupiter handover meant that Zeus was now the only strategic program being carried out by the Army, and its cancellation would mean "virtually the surrender of the defense of America to the U.S.A.F at some future date."
In May 1957, Eisenhower tasked the
While the report was being prepared, in August 1957 the Soviets launched their
With the NIE reports suggesting the existence of the gap Gaither predicted, near panic broke out in military circles. In response, the US began to rush its own ICBM efforts, centered on the
With even a few hundred missiles, the Soviets could afford to target every US bomber base. With no warning system in place, a sneak attack could destroy a significant amount of the US bomber fleet on the ground. The US would still have the
Douglas Aircraft had been selected to build the missiles for Zeus, known under the company designation DM-15. This was essentially a scaled-up Hercules with an improved, more powerful single piece booster replacing Hercules' cluster of four smaller boosters. Intercepts could take place at the limits of the Wilson requirements, at ranges and altitudes of about 100 miles (160 km). Prototype launches were planned for 1959. For more rapid service entry there had been some consideration given to an interim system based on the original Hercules missile, but these efforts were dropped. Likewise, early requirements for a secondary anti-aircraft role were also eventually dropped.[b]
Wilson signaled his intention to retire in early 1957, and Eisenhower began looking for a replacement. During his exit interview, only four days after Sputnik, Wilson told Eisenhower that "trouble is rising between the Army and the Air Force over the 'anti-missile-missile'." The new Secretary of Defense,
Shortly after taking office, McElroy formed a panel to investigate ABM issues. The panel examined the Army and Air Force projects, and found the Zeus program considerably more advanced than Wizard. McElroy told the Air Force to stop work on ABM missiles and use Wizard funding for the development of long-range radars for early warning and raid identification. These were already under development as the
The team designed a much larger missile with a greatly enlarged upper fuselage and three stages, more than doubling the launch weight. This version extended range, with interceptions taking place as far as 200 miles (320 km) downrange and over 100 miles (160 km) in altitude. An even larger booster took the missile to
The new DM-15B Nike Zeus B (the earlier model retroactively becoming the A) received a go ahead for development on 16 January 1958, the same date the Air Force was officially told to stop all work on a Wizard missile. On 22 January 1958, the
With their change of fortunes after McElroy's 1958 decision, Army General
As part of their Wizard research, the Air Force had developed a formula that compared the cost of an ICBM to the ABM needed to shoot it down. The formula, later known as the
For an answer, McElroy turned to the Re-entry Body Identification Group (RBIG), a sub-group of the Gaither Committee led by
Turning this argument about, the RBIG delivered a report to McElroy that agreed with the Air Force's original claims on the ineffectiveness of ABMs based on cost. But then they went on to consider the Zeus system itself, and noted that its use of mechanically steered radars, with one radar per missile, meant that Zeus could only launch a small number of missiles at once. If the Soviets also deployed MRV, even a single ICBM would cause several warheads to arrive at the same time, and Zeus would simply not have time to shoot at them all. They calculated that only four warheads arriving within one minute would result in one of them hitting the Zeus base 90% of the time. Thus one or two Soviet missiles would destroy 100 Zeus's. The RBIG noted that an ABM system "demands such a high rate of fire from an active defense system, in order to intercept the numerous reentry bodies which arrive nearly simultaneously, that the expense of the required equipment may be prohibitive". They went on to question the "ultimate impossibility" of an ABM system.
McElroy responded to the RBIG report in two ways. First, he turned to the newly created
|“||The problem here is the usual problem between defense and offenses, measures, countermeasures, counter-counter measures, et cetera, in which it has been my judgment and still is that the battle is so heavily weighted in favor of the offense that it is hopeless against a determined offense and that incidentally applies to our position with regard to an anti-missile that they might build. I am convinced that we can continue to have a missile system that can penetrate any Soviet defense.||”|
When this report was received, McElroy then charged ARPA to begin studying long-term solutions to the ICBM defense, looking for systems that would avoid the apparently insurmountable problem presented by the exchange ratio.
ARPA responded by forming
Project Defender, initially considering a wide variety of far-out concepts like
In the midst of the growing debate over Zeus' abilities, the US conducted its first high yield, high altitude tests –
If this were not enough, there was a growing awareness that simple
In 1959 the Defense Department ordered one more study on the basic Zeus system, this time by the PSAC. They put together a heavyweight group with some of the most famous and influential scientists forming its core, including
Throughout, Zeus was the focus of fierce controversy in both the press and military circles. Even as testing started, it was unclear if development would continue. President Eisenhower's defense secretaries, McElroy (1957–59) and
Kennedy appointed Army General
Kennedy was fascinated by the Zeus debate, especially the way that scientists were lined up on diametrically opposed positions for or against the system. He commented to Wiesner, "I don’t understand. Scientists are supposed to be rational people. How can there be such differences on a technical issue?" His fascination grew and he eventually compiled a mass of material on Zeus which took up one corner of a room where he spent hundreds of hours becoming an expert on the topic. In one meeting with Edward Teller, Kennedy demonstrated that he knew more about the Zeus and ABMs than Teller. Teller then expended considerable effort to bring himself up to the same level of knowledge. Wiesner would later note that the pressure to make a decision built up until "Kennedy came to feel that the only thing anybody in the country was concerned about was Nike-Zeus."
To add to the debate, it was becoming clear that the missile gap was fictional. The first
Nevertheless, Zeus continued slowly moving towards deployment. On 22 September 1961, McNamara approved funding for continued development, and approved initial deployment of a Zeus system protecting twelve selected metropolitan areas. These included Washington/Baltimore, New York, Los Angeles, Chicago, Philadelphia, Detroit, Ottawa/Montreal, Boston, San Francisco, Pittsburgh, St. Louis, and Toronto/Buffalo. However, the deployment was later overturned, and in January 1962 only the development funds were released.
In 1961, McNamara agreed to continue development funding through FY62, but declined to provide funds for production. He summed up both the positives and the concerns this way:
|“||Successful development [of Zeus] may force an aggressor to expend additional resources to increase his ICBM force. It would also make accurate estimates of our defensive capabilities more difficult for a potential enemy and complicate the achievement of a successful attack. Furthermore, the protection that it would provide, even if for only a portion of our population, would be better than none at all ...
There is still considerable uncertainty as to its technical feasibility and, even if successfully developed, there are many serious operating problems yet to be solved. The system, itself, is vulnerable to ballistic missile attack, and its effectiveness could be degraded by the use of more sophisticated ICBMs screened by multiple decoys. Saturation of the target is another possibility as ICBMs become easier and cheaper to produce in coming years. Finally, it is a very expensive system in relation to the degree of protection that it can furnish.
Looking for a near term solution, McNamara once again turned to ARPA, asking it to consider the Zeus system in depth. The agency returned a new report in April 1962 that contained four basic concepts. First was the Zeus system in its current form, outlining what sort of role it might play in various war fighting scenarios. Zeus could, for instance, be used to protect SAC bases, thereby requiring the Soviets to expend more of their ICBMs to attack the bases. This would presumably mean less damage to other targets. Another considered the addition of new
As work on Nike-X began, high-ranking military and civilian officials began to press for Zeus deployment as an interim system in spite of the known problems. They argued the system could be upgraded in-place as the new technologies became available. McNamara was opposed to early deployment, while Congressman
McNamara's argument against deployment rested on two primary issues. One was the apparent ineffectiveness of the system, and especially its
|“||It is estimated that a shelter system at a cost of $2 billion would save 48.5 million lives. The cost per life saved would be about $40.00. An active ballistic missile defense system would cost about $18 billion and would save an estimated 27.8 million lives. The cost per life saved in this case would be about $700. [He later added that] I personally will never recommend an anti-ICBM program unless a fallout program does accompany it. I believe that even if we do not have an anti-ICBM program, we nonetheless should proceed with the fallout shelter program.||”|
The second issue, ironically, came about due to concerns about a Soviet ABM system. The US's existing SM-65 Atlas and
In one particularly telling exchange between McNamara and Flood, McNamara initially refuses to choose one option over the other:
Flood: Which comes first, the chicken or the egg? Which comes first, Minuteman because he may develop a good Zeus, or our own Zeus?
McNamara: I would say neither comes first. I would carry on each simultaneously with the maximum rate of activity that each could benefit from.
But later, Flood managed to get a more accurate statement out of him:
Flood: I thought we had broken through this problem in this country, of wanting things to be perfect before we send them to the troops. I have an enemy who can kill me and I cannot defend myself against him, and I say I should hazard all risks within the rule of reason, to advance this by 2 or 3 years.
McNamara: We are spending hundreds of millions of dollars, not to stop things but to accelerate the development of an anti-ICBM system... I do not believe it would be wise for us to recommend the procurement of a system which might not be an effective anti-ICBM device. That is exactly the state in which we believe the Zeus rests today.
Flood: ... You may not be aware of it, but you have just about destroyed the Nike-Zeus. That last paragraph did that.
By 1963 McNamara had convinced Kennedy that the Zeus was simply not worth deploying. The earlier concerns about cost and effectiveness, as well as new difficulties in terms of attack size and decoy problems, led McNamara to cancel the Zeus project on 5 January 1963. In its place they decided to continue work on Nike-X. Nike-X development was based in the existing Nike Zeus Project Office until their name was changed to Nike-X on 1 February 1964.
While reporting to the Senate Armed Services Committee in February, McNamara noted that they expected the Soviets to have an initial ABM system deployed in 1966, and then later stated that the Nike-X would not be ready for use until 1970. Noting a "defensive gap",
On 11 April 1963, Thurmond led Congress in an effort to fund deployment of Zeus. In the first closed session of the Senate in twenty years, Zeus was debated and the decision was made to continue with the planned development of Nike-X with no Zeus deployment. The Army continued the testing program until December 1964 at White Sands Missile Range, and May 1966 at Kwajalein Missile Range.