Overview

A cluster bomb, also called a cluster munition, is a weapon that opens in flight or on impact to release multiple smaller explosive submunitions across a broad area. Some types detonate in the air to increase their lethal radius while others scatter bomblets that strike the ground; many designs are intended to wound or kill people rather than defeat armoured vehicles. The basic concept is to attack dispersed targets or cover a wide zone more quickly than single large warheads.

Design and characteristics

Typical cluster munitions consist of a larger dispenser that contains dozens to hundreds of small bomblets, each with its own explosive charge and sometimes a small fuze. The dispenser may be launched from aircraft, artillery, rockets or missiles and programmed to open at a set altitude or on impact. Because of varying manufacturing tolerances, a percentage of submunitions can fail to detonate on impact and become unexploded ordnance (UXO), posing long-term risks.

History and use

Cluster weapons have been used in several conflicts since World War II. They were employed extensively in the Vietnam War and have appeared in more recent conflicts, including in Iraq and Afghanistan. Their wide-area effect made them attractive for certain military objectives, but their long-term hazards to civilians and post-conflict communities have drawn sustained criticism. Readers can find descriptive accounts of how these weapons operate in technical summaries such as airburst and ground-dispersion reports and studies of operational use from the Vietnam era.

Humanitarian impact

Because submunitions can fail to explode on impact, they can remain dangerous for years, causing civilian casualties, limiting access to farmland, and obstructing reconstruction. Many humanitarian organizations document civilian injuries and fatalities linked to unexploded submunitions, and clearance of contaminated areas is costly and slow. Field reports and investigations from recent conflicts are available in various summaries and country case studies about Iraq and about Afghanistan.

Concern about civilian harm led to international efforts to restrict cluster munitions. The Convention on Cluster Munitions, adopted in 2008, bans the use, production, transfer and stockpiling of many types of these weapons and has been signed by over one hundred states. However, some countries have not joined the treaty and continue to possess or use cluster munitions, keeping the issue a subject of legal, military and ethical debate. For technical overviews of delivery modes and dispersal mechanics see dispenser and fuze analyses.

  • Key issues: wide-area effect, unexploded ordnance, civilian risk, international law.
  • Related topics: unexploded ordnance clearance, arms control treaties, post-conflict recovery.