From the earliest traces of mankind up to our modern civilization, weapons have been a facet of human development. Weapons development has accelerated along with other areas of technology in more modern times. In ancient times, from the dawn of humanity through the Classical civilizations of Greece and Rome, weapons were primarily extensions of an individual's strength, essentially making up for the human body's lack of natural weapons such as claws. These weapons allowed the bearer to be substantially more lethal than a similar human without such a weapon.
The Medieval period, including the Middle Ages, marked a period of distinct advancement in weaponry. Due to some of the unique influences of the period, weapons revolved around two major areas. First was that of knights. These horsemen required new weapons, as well as promoting development of weapons to defeat them. Second was that of castles. The building of castles on a large scale necessitated new weapons to help defend and attack them.
The Renaissance marked the beginning of the implementation of technological devices in warfare. The most long-lasting effect of this was the introduction of cannon and firearms to the battlefield, where they are still at the core of modern weaponry. However, many other machines of war were experimented with.
From the American Revolution through the beginning of the 20th Century, human-powered weapons were finally excluded from the battlefield for the most part. Sometimes referred to as the Age of Rifles, this period was characterized by the development of firearms for infantry and cannons for support, as well as the beginnings of mechanized weapons such as the machine gun.
World War I marked the entry of fully industrialized warfare, and weapons as well were developed quickly to meet wartime needs. Many new technologies were developed, particularly in the development of military aircraft and vehicles. World War II however, perhaps marked the most frantic period of weapons development in the history of humanity. Massive numbers of new designs and concepts were fielded, and all existing technologies were improved between 1939 and 1945. Ultimately, the most powerful of all invented weapons was the nuclear bomb.
After World War II, with the onset of the Cold War, the constant technological development of new weapons was institutionalized, as participants engaged in a constant race to develop weapons and counter-weapons. This constant state of weapons development continues into the modern era, and remains a constant draw on the resources of most nations.
The basic tasks a weapon must perform have not changed since ancient times. All weapons do one or more of the following:
- Concentrate pressure: the sharp end of a broken stone or pointed stick will apply more pressure, and do more harm, than the blunt end. A material's hardness determines its ability to apply or resist pressure.
- Store energy: an object accumulates kinetic energy as a person accelerates it, and releases this energy in a much shorter time frame upon impact, thus magnifying a person's power.
- Project force: a thrown rock or long stick allow a person to affect an adversary from a distance.
As shown by the preceding examples, even simple items such as rocks and sticks can often serve these functions better than the human body. The usefulness of such tools made their development of paramount importance for a humanity consisting of small, thinly spread, hunter-gatherer communities. The first known traces of weapons are from the stone age with flint knives, handaxes and heads for large darts. There is no evidence for handaxes being thrown, but very good evidence for them having been used to butcher animals. Instead, darts seem to have been a powerful projectile weapon: anthropologists have thrown reconstructed darts through several inches of oak using atlatls. The broad, leaf-shaped heads penetrate deeply, and easily cut arteries.
Some weapons are probably much older than the dart, although little early evidence for them exists. These include the sling and the spear. Even though these weapons are quite simple, they were a major military weapon at least until Roman times; a unit of fast-moving skirmishers could be equipped with them at very little cost. Lack of early evidence is understandable, as slings are prone to decay, and it would be difficult to prove that a particular stone has been used as ammunition. Similarly, there is less incentive to put a stone point onto a spear than a dart. A weighted spear point is a liability rather than an asset, and the greater momentum imparted by stabbing makes sharpness less critical than toughness, so that points of bone, antler, or even fire-hardened wood can make more effective spear points. Once metal became available, its toughness made spears and pikes the core of most infantry forces.
Some of the earliest evidence for arrows are from ca. 20,000 BC in the Levant (the so-called 'Geometric Kebaran' period), made with several very small sharp pieces of stone embedded in an arrowshaft. Here again, far earlier examples may have been subject to decay: for instance, some cultures make weighted arrow points by cutting a hollow reed diagonally and filling the end segment with clay.
Archery and swords have been crucial for warfare. Archery, because of the large amount of energy that can be easily stored and released using a bow, and short swords because of their lethality in close combat. Far greater energy can be stored in a composite bow than a wooden bow of the same weight due to clever mechanical design and choice of materials, but militarily such weapons were mostly limited to use in dry climates. Traditional designs are held together by animal glue (chemically similar to gelatin); moisture would weaken the glue and damage bows of this design. The long bow makes up for less exotic materials with its larger size. In another tradeoff, short swords can be optimized for either stabbing or chopping; the former focuses on pressure, the latter on energy. The gladius hispaniensis could slip through openings in armor, and Roman doctrine held that a stab wound as shallow as one inch could be lethal. The hatchet-like Greek kopis, by contrast, seems built to dismember, but its point-heavy balance might make it clumsy against comprehensive armor.
The most effective defense to traditional weapons was a fortress. The doctrines to support fortresses in the age of edged weapons may have greatly influenced medieval and noble history. Medieval siege weapons were used in countervailing doctrines, but the stave-sling and even the bow often had superior range, making them unsafe to use.
Firearms are qualitatively different from earlier weapons because they store energy in a combustible propellant such as gunpowder, rather than in a weight or spring. This energy is released quite rapidly, and can be restored without much effort by the user, so that even early firearms were much more powerful than human-powered weapons. They became increasingly important and effective during the 16th century to 19th century, with progressive improvements in ignition mechanisms followed by revolutionary changes in ammunition handling and propellant. During the U.S. Civil War various technologies including the machine gun and ironclad warship emerged that would be recognizable and useful military weapons today, particularly in lower-technology conflicts. In the 19th century warship propulsion changed from sail power to fossil fuel-powered steam engines.
The Maxim gun and its derivative the Vickers (shown here) remained in British military service for 79 consecutive years.The age of edged weapons ended abruptly just before World War I with rifled artillery, such as howitzers which are able to destroy any masonry fortress. This single invention caused a revolution in military affairs and doctrines that continues to this day. See military technology during World War I for a detailed discussion.
An important feature of industrial age warfare was technological escalation - an innovation could, and would, be rapidly matched by copying it, and often with yet another innovation to counter it. The technological escalation during World War I was profound, producing armed aircraft and tanks.
This continued in the period between the end of that war and the next, with continuous improvements of all weapons by all major powers. Many modern military weapons, particularly ground-based ones, are relatively minor improvements on those of World War II. See military technology during World War II for a detailed discussion.
The greatest development in weaponry since World War II has been the combination and further development of two weapons first used in it - nuclear weapons and the ballistic missile, leading to its ultimate configuration the ICBM. The mutual possession of these by the United States and the Soviet Union ensured that either nation could inflict terrible damage on the other; so terrible, in fact, that neither nation was prepared to instigate direct, all-out war with the other. The indiscriminate nature of the destruction has made nuclear-tipped missiles essentially useless for the smaller wars fought since. However computer-guided weaponry of all kinds, from smart bombs to computer-aimed tank rounds, has greatly increased weaponry's accuracy.
In modern warfare, since all redoubts are traps, maneuver and coordination of forces is decisive, overshadowing particular weapons. The goal of every modern commander is therefore to "operate within the observation-decision-action cycle of the enemy." In this way, the modern commander can bring overwhelming force to bear on isolated groups of the enemy, and tactically overwhelm an enemy. See military technology of the late 20th century.
Traditional military maneuvers tried to achieve this coordination with "fronts" made of lines of military assets. These were formerly the only way to prevent harm to friendly forces. Close-order marching and drill (a traditional military skill) was an early method to get relative superiority of coordination. Derivative methods (such as "leapfrogging units to advance a line") survived into combined arms warfare to coordinate aircraft, artillery, armor and infantry.
Computers are changing this. The most extreme example so far (2003) is the use of "swarm" tactics by the U.S. military in Iraq. The U.S. had instantaneous, reliably encrypted communications, perfect navigation using GPS and computer-mediated communications to aim precision weapons.
In swarm tactics, small units pass through possible enemy territory. When attacked, they try to survive, and call down immediate overwhelming showers of precision-guided air-dropped munitions for armor, and cluster bombs for enemy troops. To consolidate such a region, nearby artillery begin bombardment, and ground units rush in on safe vectors through the bombardments, avoiding them by computer-mediated navigation aids.
Thus in modern warfare, satellite navigation systems and especially computers give a decisive advantages to ordinary military personnel armed with weapons that are otherwise unremarkable.