Tactical missiles vary widely in size, weight, proportions, launch platform, and method of guidance. They are manufactured in a dozen different countries, and designed for a wide variety of missions. Even so, they have many features in common. Nearly all, for example, have the same structure: a metal tube, fitted with stubby fins for steering and stability, which contains a rocket motor, a guidance system, and a warhead. The motor nearly always uses solid fuel, for reliability and ease of storage. The warhead, likewise, is nearly always conventional rather than nuclear. A typical missile’s fins are partly or wholly movable. Like the control surfaces on an airplane (rudder, elevators, and ailerons), they alter the machine’s course by altering the flow of air around it. The control surfaces in a modern, high-performance airplane move in response to electrical signals carried by wires from the cockpit, where they are generated by the pilot’s movement of the controls. The control surfaces in a tactical missile move in response to electrical signals from the guidance system. Missiles, in other words, were using “fly-by-wire” control systems long before such systems became standard in airplanes.

The basic function of a tactical missile’s guidance system is to translate input about the relative positions of the (moving) missile and its (probably moving) target into output that will move the missile’s control surfaces just enough to keep it on target. The source of the guidance system’s input varies widely from missile to missile.Wire-guided missiles, for example, remain connected to their launchers by thin wires as fine as a human hair that unreel behind them and carry inputs from the operator. Radio-guided missiles substituted a wireless link for a wire one, but still required the operator to maintain control. Heat-seeking missiles, on the other hand, use onboard infrared sensors to lock onto and follow the heat generated by the target. Laser- and radar-guided missiles locate and follow their targets using energy (light beams and radio waves, respectively) bounced off the target’s surface. Each type of guidance system has both benefits and disadvantages. Radar-
guided missiles, for example, can be used in all weather conditions and fired from beyond visual range, but are complex and vulnerable to electronic jamming that disrupts their radar. Heat-seeking missiles are less complex and more reliable, but they can only lock onto their targets at relatively close ranges, and can be lured away from the target by flares and other intense heat sources. Wire-guided missiles are virtually immune to such “spoofing” but oblige the user to remain within visual range of the target until they hit.

Improvements in guidance-system technology gradually improved missiles’ performance as the Cold War went on. Early heat-seeking missiles could only “see” and lock onto intense heat sources like jet exhaust pipes and so could only be fired from behind a target aircraft. Later versions, with more sophisticated infrared sensors, could lock onto the friction-heated air streaming back from a target aircraft’s nose, and so could be fired from any angle. Early radar-guided missiles depended on an external radar set (part of the aircraft or ground installation firing the missile) to “paint” the target with its signals—often a difficult requirement to fulfill in the chaos of battle. Later versions carried their own radar sets, which allowed them to be used (as heat-seekers had always been) as “fire and forget” weapons. A further improvement supplemented the missile’s onboard radar with an inertial guidance system like that used on ballistic missiles. The dual guidance system allowed the missile’s radar to be used in brief bursts at critical moments, making enemy jamming more difficult.

Other missile components also evolved, though less extensively, during the Cold War era. “Hot launching,” in which the missile’s own exhaust sets it in motion, was gradually supplemented by “cold launching,” in which a charge of compressed gas (or some other nondestructive mechanism) throws the missile from its launcher before the engine starts. Cold-launch systems allowed missiles to be fired from the decks of ships, the tops of armored vehicles, and the shoulders of infantrymen in confined spaces— anywhere the hot gasses of missile exhaust would cause damage or injury. Missile warheads, originally simple charges of high explosive, also evolved into specialized forms designed for specific types of targets. Armor-piercing warheads carried specially shaped explosive charges designed to focus the force of their explosion inward. Antiaircraft warheads were designed to spray clouds of metal shrapnel through the fragile engines and fuel tanks of their targets. The United States even developed an antiaircraft missile—the Genie—with a nuclear warhead. Designed for use against Soviet bomber formations in the event of an attack on the United States, it was intended to destroy or damage many aircraft in a single blow.

The technological diversity of tactical missiles is much greater than this brief discussion suggests. The range of roles in which they have been used is also broad. Tactical missiles are, by convention, divided into four categories according to where they are launched and where they hit: air-to-air, air-to-surface, surface-to-air, and surface-to-surface. In tracing tactical missiles’ impact on warfare, however, it is convenient to blur those distinctions and focus instead on the principal types of targets at which they were aimed.

The basic goal of warfare has not changed since the days that Homer wrote about in the Iliad: inflict enough damage on the enemy’s troops to achieve your goal, while exposing your own troops to the least possible risk. The evolution of military technology reflects those goals.Weapons have grown steadily more powerful and accurate (which makes them more efficient) and steadily more able to strike at a distance (which makes their users less vulnerable). Most advances in military technology are small, incremental changes that have only a modest impact on strategy and tactics. Occasionally, however, a new type of weapon transforms both. The airplane (which added a third dimension to the battlefield) was one such weapon. The tank (which combined the mobility of cavalry and the destructive power of artillery) was another. The tactical guided missile was a third.

Even the earliest tactical missiles offered a powerful combination of attributes: destructive power, portability, and relatively low cost. Their destructive power made aircraft, ships, and tanks—the basic tools of mid twentieth- century warfare—more vulnerable than ever before. Their portability and low cost allowed them to quickly spread beyond the boundaries of the industrialized nations that built them. The United States and the Soviet Union, arming their allies against one another, shipped huge quantities of their missiles abroad. Missiles also became important in the international arms trade, with France (for example) supplying its Exocet antiship missile to the air forces of Argentina, Iraq, and other countries. Tactical missiles had, by the time the Cold War ended in 1990, spread to every nation where political tensions led (or threatened to lead) to military action: Taiwan, Korea,Vietnam, Israel, Lebanon, Iran, Iraq, Afghanistan, and so on. When war did break out in those areas, it was shaped by the widespread presence of the missiles. Nations that used them effectively (Egypt and Syria in 1973, Israel in 1982) enjoyed a great advantage over nations that did not. Even the United States (in Vietnam) and the Soviet Union (in Afghanistan) found themselves put on the defensive by enemies that had mastered the use of tactical missiles.

Tactical missiles transformed the battlefields of the Cold War era because of the threat they posed to expensive, powerful military “assets” like planes, ships, and armored vehicles. The simple fact that the missiles existed—that they might be used—forced the commanders who controlled those assets to deploy them more carefully. Ships approached enemy shorelines less frequently, and treated every unidentified aircraft as a potentially lethal threat. Bombers and attack aircraft flew high to avoid the threat of missiles, sacrificing surprise and accuracy in order to avoid crippling losses. Armored vehicles moved more cautiously, wary of opportunistic missile attacks by enemy infantry and aircraft. Commanders advancing boldly into enemy territory risked disaster if the enemy’s missiles were not neutralized first—either by preemptive attacks or by defensive measures like flares, chaff, jamming, or evasive maneuvers.

Defensive measures grew steadily more sophisticated and effective as the Cold War went on. So, not surprisingly, did the missiles themselves. Warheads became more powerful, guidance systems more capable, and missiles as systems more reliable. The threat of enemy missiles could thus be reduced, but never eliminated. Effectively using (and defending against) missiles had, by 1990, become as important to military success as controlling the high ground.