What is Combined Arms, and Why Is It Effective?

The combat power that a military force can exert in battle is not determined solely by the size of its units or the performance of its equipment. It is no exaggeration to say that employment is, in fact, the most important factor. There are various principles for the employment of military forces in combat, and one of them is combined arms.

The purpose of combined arms is to achieve greater results than would be possible if each weapon were used separately by coordinating multiple weapons based on a single concept. For example, artillery providing fire support to infantry assaulting a fortified enemy position, or tanks supporting infantry that have been halted by enemy resistance, are examples of combined arms.

Although combined arms has a long history, the tactics of combined arms as we understand them today did not develop until the 20th century. U.S. Army officer Jonathan House considers World War I to be the turning point, stating that combined arms were essential for survival on the battlefields of that time. According to House, the advantage of combined arms lies in presenting the enemy with a complex threat, making it difficult for them to respond.

In a situation where artillery shells are falling one after another, soldiers must take refuge in deep underground bunkers to ensure their safety. However, placing frontline units in such a posture makes it impossible for them to detect, identify, and engage approaching enemy infantry units. Therefore, a commander exposed to the threat of combined arms faces greater difficulty in responding than if they were attacked by only one type of weapon (for details, see [Translation Material] House, 'What is Combined Arms' (1984)).

U.S. Army officer Robert Leonhard explores the concept of maneuver warfare in his book 'The Art of Maneuver' (1991), in which he also examines combined arms in detail. Leonhard proposed organizing combined arms into three principles.

The first principle is the 'complementary principle.' Infantry, armor, and artillery each have different strengths and weaknesses; for example, infantry units can advance through terrain that is difficult for vehicles to traverse, but their movement speed is slow, and they are vulnerable when placed in open areas. Tanks move on tracks rather than wheels, giving them the ability to maneuver off-road, but they still struggle to move through extremely rugged terrain and are easily destroyed when placed in confined areas that hinder rapid movement. Mutually compensating for these advantages and disadvantages is the first principle of combined arms (1991: 93–4).

The second principle is the 'dilemma principle.' As mentioned earlier, an enemy exposed to the threat of multiple weapons finds it difficult to take optimal action to counter those threats. An armored unit exposed to the threat of aircraft can disperse its vehicles and dig into the ground to hide its tanks to protect them, but by adopting such a posture, they cannot respond when enemy tanks appear. Therefore, the commander of the armored unit is presented with a dilemma (Leonhard 1991: 94–5).

The third principle is the 'Alcyoneus principle.' Simply put, this is the principle of choosing a battlefield that is advantageous to friendly forces and disadvantageous to the enemy. Alcyoneus was a giant in Greek mythology who was invincible as long as he remained on the land where he was born, but was killed when he was pulled away from it. Leonhard argues that since infantry, armor, and artillery each have different locations where they can gain an advantage, utilizing those differences is also an important principle of combined arms (Leonhard 1991: 96–7).

Understanding Leonhard's three principles makes it clear how important combined arms is as a tactical principle for contending with an enemy on the battlefield. It can be said that modern tacticians are required to grasp the performance and characteristics of a wide variety of weapon systems and consider how to employ them effectively according to the tactical situation.

Related Articles