Harassing fire

Harassing fire is a form of psychological warfare in which an enemy force is subjected to random, unpredictable and intermittent small-arms or artillery fire over an extended period of time (usually at night and times of low conflict intensity) in an effort to undermine morale, increase the enemy's stress levels and deny them the opportunity for sleep, rest and resupply. This lowers the enemy's overall readiness and fighting ability, acting as a force multiplier for the harassing force.

As the name suggests, harassing fire is undertaken as an extreme form of nuisance without a major effort to produce significant casualties or to support a larger attack. The intent is to merely ensure the enemy can never fully rest or attend to non-combat related tasks and must always be alert and in cover from incoming fire. For this reason, harassing fire is often conducted at night (or around the clock if resources allow) and by a small number of guns or artillery pieces rather than the whole contingent. The denial of sleep and constant alert state it induces is physically and psychologically unsustainable by infantry forces for any length of time, and eventually causes severe degenerative stress and degradation of the force's combat abilities. For this reason, it has been a standard and efficacious tactic used since the introduction of the projectile weapon.

Harassing fire became commonplace after the invention of the catapult and trebuchet, which could be used to hurl a variety of harmful objects over fortified walls during the siege of a city or castle. Since such a siege could drag on for months or years if the attackers were unable to forcibly breach the walls, an alternative plan called for patience coupled with regular harassing fire in an effort to induce the defenders to surrender due to low morale, disease, and starvation. Aside from lethal projectiles such as stones and iron balls, the artillery of the time would also throw harassment projectiles: rotting bodies (both men and animals), plague-infected corpses, piles of human excrement, beehives and the severed heads of captured enemy prisoners of war, all in an effort to harass and discourage the besieged defenders until they surrendered.

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