The increasingly larger force of operational TRIDENT submarines provide the primary base for U.S. deterrence of a massive Soviet nuclear strike against the United States. The inability of the Soviets to target and destroy this strategic nuclear weapon system with any degree of certainly, and the assured capability of TRIDENTs to retaliate massively after a Soviet strategic nuclear strike makes them unquestionably the most essential part of the U.S. Triad of strategic weapon systems.
Land based ICBMs and “stealth” bombers remain so susceptible to destruction in a surprise enemy strategic nuclear strike as to make these other two legs of the Triad only hedges against the possibility of an anti-submarine breakthrough by the Soviets. But at this time this is a highly improbable happening, as can be shown.
This present situation is clearly recognized and is evidenced by President Bush’s acceptance that the TRIDENTs mutual assured destruction capability continues to be the base for the U.S. strategic deterrence strategy. The TRIDENT’s assured destruction of enemy counter-value targets rather than counterforce targets is evidently considered sufficient to deter Soviet strategic aggression.
What is happening in today’s climate of reduced budgets for U.S. strategic systems along with a serious attempt to reduce nuclear warheads through the START process, is a balancing of the great need for force modernization in all three parts of the Triad. The Midgetman and rail mobile Mx, the Stealth B2 bomber, and the TRIDENT’s D-5 missile are seemingly essential to the force modernization programs. What these modernizations represent are: a relatively low cost (about $30 million per copy) single big warhead ICBM with a hard target kill capability; a rail mobile ICBM with at least 10 counterforce MIRVs per missile; a low radar-profile, long range (at least $600 m. per) nuclear bomber; and a submarine launched 8 MIRV missile with high accuracy giving it a counter-force kill capability. Importantly, the submarine launched D-5 missile with its hard target kill capability should be operational in late 1989, the Midgetman is expected to be placed in silos in the mid to late ’90s, the rail mobile Mx should be ready for use in the mid ’90s and the Stealth bomber might be expected in approximately the same time frame.
But before proceeding further, it should be recognized that the word TRIDENT has caused semantic confusion by being used indiscriminately to mean the submarine, its weapon, and even the total weapon system involved. Correctly, the term TRIDENT, as used herein, applies to those U.S. strategic nuclear submarines which are supplanting the POSEIDON submarines in the U.S. Triad. There are presently ten of these submarines operational with five more abuilding, plus one more funded. Importantly, TRIDENTs are replacing overage POSEIDON boats. And the term TRIDENT does not apply to the ballistic missile it carries nor does it imply the total weapon system unless so qualified.
There are two major concerns relative to the TRIDENT weapon system which are held by the planners for strategic nuclear war. They are an ASW breakthrough which would compromise the TRIDENT submarine’s survivability; and the assured communications between the National Command Authority and TRIDENTs at sea on patrol.
As to the first concern, what is feared most is that there would be a breakthrough in non-acoustic detection of submarines. The U.S. submarine community has repeatedly stated that there is now no imminent breakthrough in the technology involved with non-acoustic detections — nor is there any for the foreseeable future. Yet, as detailed by Tom Stefanick in his article Non-Acoustic Detection of Submarines in the March 1988 Scientific American, at least seven nonacoustic submarine signatures apparently exist most of the time and might be exploited by both the Soviets and the U.S., as a means to detect totally submerged submarines. They comprise the magnetic anomaly effect, the infra red scar, the Bernoulli dynamic hump on the surface of the ocean, the radioactive particle trail, the bioluminescence created by small sea life, the inner waves created in thermal layers, and the trail of tiny bits of peeled off submarine debris. Stefanick’s detailing of the phenomena concerned along with the technology, as known today, to usefully record these signatures, shows that although all seven signatures are possibly detectable and distinguishable from similar ocean anomalies, when the TRIDENT was operating at shallow depths, they are not detectable in a practical sense if the TRIDENT operates well below the surface. Nor will further development of known technologies produce any more than very small increments of improved detection capability. Hence the non-acoustic phenomena exist but normal 1RIDENT patrol operations so dilute their effects as to make TRIDENTS non-acoustically non-detectable — with a continued assured survivability in the ASW environment at least through the end of this century. With 70% of the TRIDENTs continuously at sea, few can be destroyed by a surprise attack.
The assured communications from the National Command Authority to TRIDENTs on patrol has been equally suspect as a form of degradation of the seabased leg of the Triad. Little recognized is that the ELF (extremely low frequency) system in use provides one-way information to deeply submerged TRIDENTs – even under conditions of nuclear war’s EMP (electro magnetic pulse) effects. One is led to believe, however, that the slow data rate — enough to spell out three letters of the alphabet in about 20 minutes — makes this system no more than a “bell ringer” to alert a TRIDENT submarine to rise to a shallower depth in order to receive communications from VLF transmitters, or UHF transmissions via satellite. Significantly, ELF communications of merely two letters can provide over 600 variant instructions compiled in a code book. About all that cannot be readily detailed to a submarine in two-letter codes are changed coordinates for missile targets. Importantly, only in a massive nuclear strike is the ELF transmitting system likely to be targeted and put out of commission. But then a TRIDENT’s massive retaliation becomes virtually automatic with weapon release activated by any one of a large number of alerting systems — broadcasting a firing order. The robustness and multi-frequency means for communicating to TRIDENTs from U.S. shore installations is convincingly detailed by John Weinstein, the chief, Policy and Programs at the U.S. Nuclear Command and Control System Support Staff, in his article Command and Control of Strategic Submarines in NATIONAL DEFENSE, March 1989. He emphasized that: “Electro Magnetic Propagation (from nuclear bursts) does not disrupt communications across the entire radio spectrum, and that numerous Emergency Action Message dissemination modes are EMP hardened.” He concludes, “‘The connectivity of SSBNs and the reliability of their weapons assure the National Command Authority that the sea-based Triad leg can and should be relied on to maintain the deterrent balance in any arms control regime.”
If START achieves a 6,000 nuclear warhead limit for strategic weapon systems — and it seems likely to do so in light of the present attitudes of the superpowers relative to cutting the total number of warheads at least in half — then the split of warheads between the three parts of the Triad becomes a critical issue.
Since Midgetman involves only a single warhead per ICBM and only a relatively small number of Midgetman missiles (300500 in most analyses) are programmed, there are not many warheads involved in this force modernization. The small numbers of rail mobile Mx’s would also require only a small fraction (500 at present) of the 6,000 warheads, while Stealth bombers, which are counted as “a single warhead” per plane, would use up an even smaller fraction. Thus, the number of warheads allotted to the TRIDENT system can be far larger than a one-third share of the pool of nuclear weapons used by the Triad. This is also practical in a period of declining budgets because an 8-warhead missile provides a far less costly way of getting warheads on target than a single-warhead missile.
A program of 18 TRIDENTs using 3456 warheads (at 8 MIRVed warheads per ballistic missile) has seemingly been the lowest conceivable rational number of TRIDENTs for a U.S. strategic deterrence posture in the ’90s. Then, no other types of SSBNs, i.e. POLARIS or POSEIDON, would remain in commission.
But only 18 strategic submarines in the U.S. inventory is also considered to be a dangerously low number – because the fewer strategic submarines in operation, the greater is the Soviet ASW effort which can be focussed against each submarine at sea. Using active sonar as well as passive detection systems, considerable numbers of Soviet ASW units including satellites, diesel submarines, SURTASS-type ships, etc. can be mustered to hound down small numbers of TRIDENTs at sea — at any one time.
Eighteen TRIDENTs are seemingly a minimum and involve, with their 8 warheads per launch tube, over 3400 of START’s probable 6,000 warhead figure. But this allocation should not be unreasonable to the U.S. START negotiators. Their worry, since they recognize TRIDENTs using C-4s or D-Ss as the basic U.S. deterrence system, is that Soviet ASW forces might reasonably overwhelm a small number of TRIDENTs or that an ASW technological breakthrough might seriously degrade the survivability of the TRIDENT system — which is depended upon so heavily by the U.S. for national security.
Eighteen TRIDENTs seem — if Soviet ASW efforts were concentrated against them — a marginally low number for the seaborne leg of the Triad. Hence, how to increase this number by a few submarines should be under consideration. A war between the superpowers with a massive strategic nuclear exchange and catastrophic devastation of the U.S. and Soviet homelands, appears to be highly unlikely. Hence, a war with more discreet use of strategic nuclear weapons must be considered.
In a war without massive nuclear exchange, the use of strategic nuclear weapons is likely to involve only enough warheads on critical targets to politically influence the outcome of a phase of a war or cause its settlement on favorable terms. Ending a war by devastation of the superpowers’ countries seems no longer at issue. To launch a single C-4 with its eight warheads as a response to a Soviet use of only a few strategic missiles — or in reply to an accidental firing of a nuclear weapon – is likely to cause a good deal of overkill which would only induce further use of strategic weapons by the Soviets.
Having single-warhead strategic missiles is thus a desirable capability for political management of a limited war. But such a single warhead missile must have a high degree of survivability, both before launch and in its trajectory, and it should be usable after careful deliberation — to optimize the discreetness of its use while maximizing the political impact from the target it destroys.
Again it would be the TRIDENT at sea that could best provide an assured readiness for limited response and offer the luxury in timing to permit carefully thought out political implications for a missile’s use, while the TRIDENTs missile would be more difficult to intercept because of its shorter range to its target and its possible 360″ attack direction due to any TRIDENT on patrol being available for selection as the firing platform. Midgetman missiles being used for the same sort of selective response would be far more susceptible to interception by a nuclear weapon because of the limited corridor through which the land-based Midgetman would be fired. Thus, a few single-warhead C-4s or D-5s seem to be indicated for loadout per TRIDENT submarine. This would maximize the concept of a fleet-in-being in time of war which could best control the war’s progress and conclusion. But with the firing of a single missile from a 1RIDENT the risk then of losing the rest of the 1RIDENT ‘s load of weapons seems great, due to the disclosure of the 1RIDENT’s firing position to enemy forces — satellites, radars, infra-red detectors, etc. 160 nuclear warheads lost for a few warheads used? But it should be recognized that a single missile can be fired from any one of many TRIDENTS which would be deployed around the perimeter of the Soviet Union. Thus, firing of a missile could be planned from a sector which was not under observation, with a discreet timing to prevent detection by satellites in their known trajectories. Firing a single warhead missile from parts of the Indian Ocean, for example, would not be likely to disclose the TRIDENT’s position until the TRIDENT had moved well clear of its firing position.
All that needs doing, to make the 1RIDENT system compatible with START objectives, is to remove the assumption that every missile carried by a 1RIDENT will have eight warheads and substitute a technique for counting the number of warheads on each missile. This would eliminate the possibility of having to cut the TRIDENT force by one submarine in order to stay within an arbitrary limit like, for example, the 3400 weapon limit. This would also allow each submarine to cany a few single warhead missiles giving them more political clout in protracted wars and at the same time make possible a force goal of about 20 TRIDENTs – a safer, more survivable number in light of Soviet ASW strength today.
The total program for TRIDENTs — while conforming to the constraints of budgets and allotted U.S. nuclear warheads – has been designed to respond to a necessary level of national security, through the ’90s and beyond the year 2000. However, by the mid ’90s, at least three TRIDENT submarines would be undergoing overhauls, at any point in time. Such TRIDENTs would be of no use to the underseas strategic leg of the Triad — since at the outset of a national emergency, they could not be made operational for many months. TRIDENTs in overhaul would thus be incorrectly counted as having 576 available warheads, making the total force of TRIDENTs almost 17% deficient in expected wartime potential.
It should then be reasonable to have a TRIDENT program of three more TRIDENTs than that needed to utilize the some 3400 nuclear warheads which appear to be a logical distribution of STARTs proposed level of 6000 nuclear warheads for the sea-leg of the Triad.
Big Pluses for TRIDENTs
• They are manned by a higher grade of personnel than any other comparable strategic weapon system.
• There is no public resistance to the basing of nuclear warheads at sea on TRIDENTs.
• TRIDENTs do not encroach on precious land assets of the U.S. nor do they effect the environment or ecology of the United States.
• TRIDENT’s missiles tend to have shorter flight times and lesser ranges to their targets.
• And conversely, can strike targets further inland.
• The TRIDENTs command and control is far more difficult for the enemy to focus his electronic warfare efforts against — because of the TRIDENT’s unknown location.
• An increasing knowledge of how to use the anomalies of the oceans to remain covert is increasing their survivability on patrol.
• TRIDENTs are the quietest of nuclear submarines in the world today.
- TRIDENTs are rarely forced to operate in any mode except a totally covert one.
• A significant quieting of enemy attack submarines does little to increase their threat against TRIDENTs — iCs a matter of a needle trying to find another needle in a haystack.
• TRIDENTs should be considerably less susceptible to sabotage than land based systems.
• The great areas of the oceans in which TRIDENTs patrol spreads out enemy ASW effort excessively.
• Electronic warfare has little effectiveness against underseas systems.
• Similarly, nuclear warfare should have little effect on the TRIDENTs at sea.
• TRIDENTs provide a fine and flexible control of the tempo of strategic war.
• In summary, the reliance on the sea based leg of the Triad must be maintained and the modernization of this leg by means of the TRIDENT program and its most modem weapon, the D-5, should have a high priority, particularly in this time of limited budgets for strategic weapon systems, and arms control efforts. A singlewarhead SLBM option could increase TRIDENTs useful flexibility and, within START constraints, make possible deployment of some additional TRIDENT platforms. A 20-TRIDENT force would both enhance U.S. capabiJity against Soviet ASW systems and provide valuable growth potential in the event START were to collapse.
Dr. Jon L. Boyes and W. J. Ruhe