Nuclear explosives are unquestionably the most powerful weapons known to humankind. However, that does not imply that they are the last stage in weapons development, any more so than were the bow, the rifle, and the airplane. Military planners are finding that explosive force is no longer the sole arbiter of military victory—a small amount of force applied at the right time and the right place can sometimes achieve the same result as a nuclear weapon. With overwhelming conventional military superiority, the United States should be the last country to consider the use of a nuclear weapon—once we use a nuclear weapon, we become fair game for someone else to use one against us. Nuclear weapons represent the ultimate “big stick” advocated by Theodore Roosevelt, a stick that is always understood to be present, but a stick whose primary purpose is to deter the actions of others rather than to attack.
An analogy may help to clarify the changing role of nuclear weapons in the twenty-first century. During the 1930s, the United States Navy considered the battleship the primary instrument of sea power, an essential element in checking Japanese expansionism in the Pacific. Great effort was invested in developing bigger guns and faster ships under the theory that a major naval engagement would be won by the side that could deliver a lethal bombardment outside the range of the enemy’s weapons. Leviathans of forty thousand tons displacement were constructed with guns capable of shooting a one-ton projectile twenty miles or more with impressive accuracy. However, the admirals got it only half right. There was an urgent need for ships to meet the threat of Japanese expansion, but the navy needed aircraft carriers rather than battleships. Pearl Harbor tragically demonstrated that a single-engine aircraft carrying a torpedo or bomb could attack and sink a heavily armed ship thousands of times its size. The largest battleships ever constructed were sunk by aircraft rather than by big guns, even though a single hit from those guns would obliterate the aircraft.
JUST AS CHANGES in technology rendered the big-gun battleship obsolete, changes in technology are rendering nuclear weapons unnecessary for some military missions. There are three new technologies that can augment or even replace our reliance on high-yield nuclear weapons:
Advanced conventional weapons on ballistic missiles
Electronic and cyber warfare
Low-yield nuclear weapons on precision-delivery vehicles
Advanced Conventional Weapons on Ballistic Missiles
Some of the soft point targets that are currently targeted by nuclear weapons could be destroyed (or at least rendered ineffective) by a nonnuclear round delivered with high accuracy. For example, a SCUD launcher with a biological warhead could be destroyed by hitting the control panel, the launch rails, or other critical components of the system. Such an attack would be more effective at eliminating the SCUD threat than would a nuclear weapon, since a nuclear explosion might actually spread the chemical or biological agent over a wide area, defeating the purpose of the mission.
Some hardened underground bunkers cannot be destroyed by conventional bombs, even if they are placed right on top of the facility. But a high-velocity warhead falling from space would have sufficient kinetic energy to drive a lethal shock wave some tens of yards into the ground. The reasoning is simple: An explosion on the surface sends its energy into all directions so that only a fraction of that energy is directed downward to the underground target. Conversely, when an object strikes the surface almost all its momentum is transferred in the direction of the warhead’s motion—down.
As an example, a properly designed warhead falling from high altitude can hit its target with a velocity of seven thousand feet per second or more. For a 500-pound warhead, that translates to an equivalent explosive force of 250 pounds of TNT. It may not even be necessary to put explosives in the warhead—a lump of iron would suffice, since it is the momentum that will cause the damage rather than an explosion.
There are several ways that such a warhead could be delivered. Intercontinental ballistic missiles, such as the existing Minuteman III with a guidance upgrade, could deliver a lethal package across the globe in less than an hour from receipt of an order to launch. Land-based missiles have the advantage that the launch order could be delivered on a separate communication circuit to a separate set of missiles, eliminating even the possibility that a nuclear weapon might be launched by mistake.
A common criticism of conventionally armed ballistic missiles is that the observation of such a launch from an orbiting satellite could trigger an overwhelming nuclear response from Russia, China, or some other nation. However, one can envision communication protocols similar to those used to announce space launches, procedures that would calm the fears of the most nervous adversary. Also, it would be clear to most nuclear-capable countries that the trajectory of the single launch was not aimed at them. Finally, nuclear adversaries know that they could respond to a single nuclear-armed missile with dozens of their own. To provide even more assurances, we could have international observers at the control centers of conventionally armed missiles so that military officers from the other nuclear powers would be in continuous contact with their home countries and able to advise them of a conventional launch. These observers could even inspect the missiles to verify that they did not carry nuclear weapons.
Land-based missiles have the disadvantage that, because of the relative positions of the United States and its potential adversaries on the globe, some targets may require the missile to fly over countries that refuse permission for such overflight. For this reason we should consider putting conventionally armed missiles on submarines and surface ships, and assigning them to forward-deployed land units. Mixing nuclear and nonnuclear warheads on a Trident class ballistic missile submarine may be inadvisable due to the difficulty of assuring that there would be absolutely no chance of mistakenly launching a nuclear round when a conventional round was intended. However, the United States is modifying four ballistic missile submarines for conventional use (so-called SSGNs), and it would be possible to mount conventionally armed ballistic missiles on these ships with no danger of nuclear confusion. Just as reassurances can be provided to jittery countries for land-based launches, similar reassurances could be provided for submarine-based launches.
Two types of missiles could be considered for naval use—the capable and proven Trident D5 and a new or modified missile, perhaps one with a shorter range. The D5 missile was designed to be launched from Ohio class ships, and it has an outstanding record of reliability and great flexibility in targeting. It can be fired from any ocean in the world and has an accuracy that, combined with appropriate terminal guidance systems, would be adequate for conventional missions.
Short-range missiles could be fitted into the launch tubes of the converted SSGNs and could also be mounted on surface ships such as cruisers and destroyers. The Standard Missile, venerable but quite capable with its many upgrades, is one possibility, as are modifications of existing land-based missiles. One could also consider the design of a purpose-built missile for precision-strike applications. A potential limitation to new conventionally armed ballistic missiles is the proscription, signed into a treaty between the United States and Russia in 1988, against the deployment of missiles that have intermediate ranges between nineteen hundred and thirty-four hundred miles. This agreement, a relic of the Cold War, could be modified or dropped altogether since its motivation was to forestall the installation of nuclear-tipped missiles in Europe rather than conventional missiles aboard ships.
Ground units could be equipped with short-range missiles that regional commanders could control. These weapons would suffer few or none of the potential political problems associated with the launch of land-or sea-based intercontinental ballistic missiles, and with modern command and control systems, they would be an incredibly valuable tool for eliminating high-value, time-urgent targets.
Air delivery of high-velocity weapons, or other advanced conventional ordnance, is also a possibility. While a bomb falling from an aircraft, even one flying at very high altitude, does not achieve the impact velocity of a warhead falling from space, rocket-assisted warheads could be employed to increase free-fall velocity to a usable range. Also, aircraft can be equipped with other types of ordnance specifically designed for special classes of targets. The Defense Threat Reduction Agency (DTRA) has developed advanced explosives that perform with several times the efficiency of conventional munitions. These mixtures, termed “thermobarics,” burn more slowly than a normal explosive, giving the molecules more time to release all their energy into the target. DTRA has also developed exotic chemical mixtures designed to neutralize chemical and biological weapons. These and other ideas could be used in warheads and bombs intended to destroy targets that would otherwise require a massive nuclear explosive, keeping the battle firmly on the conventional level while achieving the required military objectives.
Advanced conventional weapons cannot completely replace nuclear weapons—some targets are simply too hard to be destroyed by anything less than a nuclear explosion—but they can replace nuclear weapons in many missions and would provide enhanced capability without crossing the nuclear threshold. Today, when confronted with the immediate use of weapons of mass destruction against our cities or military forces, our only options are to do nothing or launch a preemptive nuclear attack. New technology offers better solutions.
Electronic and Cyber Warfare
Nearly every country in the world depends on electronics to wage war. Even low-tech battles involve radios, GPS location systems, and computers to help aim artillery. Modern armies use sophisticated computer networks to apply the right force in the right place at the right time. The command center of a modern U.S. Army unit looks like a space launch control facility—rows and rows of computers with people combing through real-time satellite images of the battlefield, data from unmanned aircraft, and reports from ground forces. Commanders can see tanks or infantry coming and move just the right amount of force to counter the threat, avoiding ambushes of our forces and saving huge amounts of money in not having to hold massive reserves for “just in case” scenarios.
Rendering these capabilities inoperative would seriously impair the capability of any fighting force, effectively rendering it blind and deaf. This is true for our high-tech forces, but it is even truer for countries ruled by dictators, where decisions are made only at the highest levels and where personal initiative on the part of frontline battlefield commanders is discouraged. The United States found in both Gulf wars that enemy units cut off from central command in Baghdad just evaporated into the desert—without specific instructions they were unwilling to take even the most obvious military action. In contrast, our forces are trained to operate independently if cut off from central command. We use technology as an aid to, rather than a replacement for, the capabilities of our officers and enlisted people in the field.
Jamming, or the purposeful broadcasting of an intense radio signal to interfere with communications, has been practiced since the dawn of radio. So too has eavesdropping on enemy signals in an attempt to anticipate its actions. Elaborate ground-and space-based systems have been developed to intercept signals from around the world; one reason that supercomputers were invented was the need to break the codes in which these signals are sent. Almost any signal that is broadcast can be intercepted, and given enough time, all but the most heavily encrypted can be deciphered.
Electronic warfare goes well beyond signal interception and jamming. Electromagnetic weapons—devices that emit a radio or microwave pulse sufficiently intense to destroy enemy electronics—have been fielded by several nations. Russia may have developed this technology to its highest point, especially in the form of microwave generators powered by compact high-explosive-driven power supplies. These devices use an explosive charge to compress a magnetic field, turning the chemical energy of the explosive into electrical energy that can be used to power a microwave transmitter. Some are as small as six inches in diameter and eighteen inches long and produce radio pulses of hundreds of kilowatts. Others are more than thirty-six inches in diameter and many feet long and could produce pulses with more power (for an instant in time) than all the electrical generators in the world put together. During the 1990s, Moscow cut off most of the funding to some of the Russian laboratories working in this area. To get money to live, they sold microwave weapon technology to other countries, most notably China, France, and the United States.
THE DISASTROUS EFFECT of unauthorized entry into computer networks has been repeatedly demonstrated in the commercial sector as hackers have planted viruses, worms, and other network attack software on the Internet. Businesses have lost tens of millions of dollars through downtime, lost revenue, and the need to replace credit cards whose numbers have been compromised. Experts in computer security maintain that the advantage remains with the attacker and that defensive measures such as firewalls and virus scans are temporary at best. Data encryption can help, at the expense of speed, but few organizations or even countries have the sophistication to create an essentially unbreakable code.
There are three approaches to computer network attack: surveillance, modification, and destruction. Surveillance is intended to find out what the adversary is doing, such as what orders are being given to whom and where key targets are located. Skillfully conducted, computer surveillance can be performed without the adversary ever knowing that it is happening. The value of such clandestine surveillance can be immense—if you know that a given military unit is being sent to a given location, then you can deploy your own forces to counter it, eliminating the necessity of searching, keeping large numbers of your own troops in reserve, and so forth.
In addition to just listening, it is also possible to inject your own information into an adversary’s network, right up to the point of directing enemy troops into a trap or ordering them to stand down from attacking your own forces. The ability to mimic orders from central command requires considerably more skill than simple surveillance, since orders may be encrypted or may contain special authentication codes. However, amateur hackers have successfully inserted messages on the commercial Internet, despite security measures installed specifically to make it impossible for them to do so. Professionals can presumably do even better.
Destruction of computer networks can take the form of erasing data on storage media, disconnecting vital nodes, and inserting a virus that will propagate through and incapacitate the network. It is not necessary to physically destroy the equipment—it might be sufficient to make it inoperative during critical periods. Denying an enemy the opportunity to communicate with and control its forces can sometimes render them ineffective and accessible to attack.
The fundamental problem with electromagnetic weapons of all varieties is that they typically produce a “soft kill,” or one that is not always observable from a distance. Perhaps the microwave weapon or the computer attack was successful, and perhaps it was not—how much credence would a commander be willing to give a theoretical probability when lives are at stake? Also, microwave and other electromagnetic weapons more frequently result in “upset” rather than destruction. The equipment is not destroyed, but computers need to be rebooted and communication links reset. While this type of upset could be catastrophic in a modern fighter jet moving faster than the speed of sound, it might be only an annoyance in a field artillery unit that could rapidly rejoin the fight.
Low-yield Nuclear Weapons on Precision-delivery Vehicles
In the previous chapter, we noted that very few targets require more than ten kilotons of explosive energy for their destruction. This is a small fraction of the energy of most strategic weapons, the yields of which are often in the one-hundred-kiloton to megaton range. However, fearing that any work on new nuclear weapons, even those with lower yield, could ignite a new nuclear arms race, Congress has been reluctant to fund the development of weapons that are more attuned to the strategic realities of the future. One argument used by opponents of change is that, by reducing the yield, nuclear weapons become more “usable” and present a greater temptation to military commanders to cross the nuclear threshold. (Recall that commanders can merely recommend—only the president of the United States can authorize the use of nuclear weapons.) This fear has been exacerbated by some defense analysts who argue for a continuum between conventional explosives and nuclear weapons, with the implied notion that low-yield nuclear weapons might indeed be usable if the collateral damage associated with them is made sufficiently small. I believe that these arguments are seriously flawed and fail to appreciate the essential elements of strategic deterrence. I strongly believe that the United States should do everything in its power to increase the nuclear threshold, to increase the mystique associated with a nuclear detonation, and to increase the fear that any country that uses a nuclear weapon outside of the direst circumstances of national survival is committing a grave international crime. This is more than altruistic thinking—it is in our practical interest to limit the use of the only weapon that could inflict tactical defeat on our forces. The United States can win any battle, any time, so long as the adversary does not employ nuclear weapons against us. One way to make sure that it does not is to tirelessly emphasize the fundamental difference between nuclear and conventional weapons and to stress that any use of nuclear weapons could trigger an immediate and devastating response on the part of the United States.
One notion that gains occasional notoriety is the idea of a “micro-nuke,” or a very small nuclear explosive whose yield is measured in tons or tens of tons. This type of weapon falls into the category of minimal utility and maximal cost. A nuclear explosion of this yield does not produce effects substantially greater than those that can be achieved with advanced conventional weapons, but it gives the user the stigma of having crossed the nuclear threshold, thereby legitimizing the use of much larger nuclear weapons against it. It is unfortunate that such proposals continue to cloud the real debate on the future of our nuclear forces.
Having said this, for deterrence to have any value there must be a perception, on both sides, that nuclear weapons will be used in certain extreme circumstances and that they will function as designed if called upon to do so. Those with a legal turn of mind sometimes attempt to pin down governments on the exact conditions that would prompt nuclear use, failing to realize that another part of deterrence is a purposeful ambiguity that keeps an adversary from taking risks. Suppose another country mounted a biological attack on the United States. Would we respond with nuclear weapons? Perhaps, perhaps not, but the attacker would not know beforehand and might shy away from the idea of an attack just on the possibility that we might use nuclear weapons. It may be that we can handle the problem through conventional means, by destroying their weapons facilities so that they cannot mount a second attack. Using a nuclear weapon in that case would be unnecessary. On the other hand, if we had unambiguously said that any biological attack would trigger a nuclear response, the enemy would put us into the position of having to carry out that threat or lose face, decreasing confidence that we would ever use nuclear weapons and emboldening them to try more aggressive attacks in the future.
It is ironic that those who most object to the existence of nuclear weapons steadfastly insist that our unnecessarily destructive weapons remain in the stockpile and that lower-yield systems should not be deployed. Congress has repeatedly cut off funding for research and development of weapons with lower yields or those with added safety features. Anti-nuclear groups have sought to characterize any change in our nuclear stockpile as tantamount to a unilateral resumption of the nuclear arms race, forgetting that Russia has announced that it is actively pursuing new weapons technology and deploying new nuclear weapons on new missiles. It seems to me that these arguments are forcing the United States to continue a policy of mutually assured destruction, one that uses much greater force, with potentially far greater civilian casualties, than is necessary.
Intelligence
Perhaps the single most important element of the future strategic equation is accurate and timely intelligence—no amount of precision or explosive power will make up for not knowing the existence and location of dangerous targets.
The United States spends approximately $40 billion per year on intelligence, but we have failed to predict many of the history-changing events of the past three decades. No major intelligence agency confidently predicted the demise of the Soviet Union, the terrorist attacks of September 11, 2001, or the correct status of weapons of mass destruction programs in Iraq. Much has been written about the causes of these failures, but most of the problem seems to rest in three areas: the value attached to information obtained via clandestine means, the lack of scholarly analysis, and the increasing technological capability of other countries.
First, many intelligence agencies still believe that their job is to uncover secrets when their most important mission should be to gather accurate information. Analysts still associate the value of a piece of information with the means that was used to obtain it—a photograph obtained by a secret spy satellite is often considered more important than a picture clipped from a foreign newspaper. But even the most sophisticated spy satellites can be spoofed, as the Serbs did during the Balkan wars by constructing plywood silhouettes of tanks and troop carriers.
Sometimes governments publish information that they want other people to know, as when the Indian BJP party announced that, if elected, it would perform a nuclear weapons test. Many American analysts rejected this information because it had not been “confirmed” by intelligence sources, missing the point that the government was making an important statement right out where everyone could read it. Not everything in the newspaper is true; neither is everything collected by secret means. The goal of intelligence is to sift through all the information available, seeking out consistencies and obvious fallacies to construct the best picture possible.
We must also be more sensitive to the type of information that we seek. There was a time when it was imperative for the United States to know how many missiles the Soviet Union had, their location, and their operational status. The Soviets refused to provide this information, so we made huge investments in satellite systems so that we could get it ourselves by what became known as “national technical means.” Today, many of our most serious security issues involve the intentions of people, information that is not observable from space with even the most sophisticated satellite. What motivates a young man or woman to become a suicide bomber? How can we anticipate the attack of insurgents? One modern management fad insists that “if it can’t be measured it doesn’t exist,” a manifestly ridiculous notion when applied to the modern security environment, where it is often the will of a few individuals, rather than physical numbers or weaponry, that is most critical in determining their actions.
The second gap in modern intelligence relates to inadequate analysis of the data that we do have. During the 1990s, the intelligence community lost some of its best analysts—many of whom had spent decades studying particular parts of the world—to retirement, resignation, or reassignment. It is unfortunate that modern methods of personnel management sometimes shift people within an organization faster than they can develop expertise in any one area, leading to poorly informed judgments that could have disastrous consequences. The fundamental failure to project the status of Iraqi WMD capabilities was partly due to this practice, but one can easily imagine the opposite danger of not recognizing a real problem in its early stages. I have seen intelligence reports that missed key points because the people who wrote them lacked the technical knowledge to understand what they were analyzing. Conversely, I have read reports that made the adversary ten feet tall—essentially superhuman—by assuming that he had much more capability than he actually had. The ability to critically evaluate intelligence data takes time to develop, and the intelligence community must recognize the need to invest over the long term with individuals who can weigh the pros and cons of each argument, people who are able to distinguish between what is known and what is inferred.
Finally, modern intelligence requires a higher level of technical competence than ever before. Gone are the days when we could hire a retired air force test pilot to get an informed opinion of the latest Soviet fighter jet. Today we are assessing a country’s ability to do gene splicing, nanotechnology, and other high-tech activities. While many agencies bring in nationally recognized experts to help in technical evaluations, we must strengthen the ties between the intelligence community and the academic and industrial research sectors to provide the maximum assurance against technological surprise.
This is an urgent call to action—if we know that a danger exists, we have the capability to eliminate it. However, if we do not know that it exists, then even our most powerful weapons are of little use. As we found in Iraq, misinterpreting intelligence can have disastrous consequences. It is the policy of the United States to use force only as a last resort, and then to use the minimum force required to accomplish the mission. Better intelligence will advise us on the nature of the threat, and advanced weapons technologies will enable us to neutralize that threat with minimal damage to both sides.