Threat to civiliansWhile all weapons are dangerous, cluster bombs pose a particular threat to civilians for two reasons: they have a wide area of effect, and they have consistently left behind a large number of unexploded bomblets. The unexploded bomblets can remain dangerous for decades after the end of a conflict.
Cluster munitions are opposed by many individuals and hundreds of groups, such as the Red Cross, the Cluster Munition Coalition and the United Nations, because of the high number of civilians that have fallen victim to the weapon. Since February 2005, Handicap International called for cluster munitions to be prohibited and collected hundreds of thousands of signatures to support its call. 98% of 13,306 recorded cluster munitions casualties that are registered with Handicap International are civilians, while 27% are children.
The area affected by a single cluster munition, known as its footprint, can be very large; a single unguided M26 MLRS rocket can effectively cover an area of 0.23 km2. In US and most allied services, the M26 has been replaced by the M30 guided missile fired from the MLRS. The M30 has greater range and accuracy but a smaller area of coverage. It is worth noting that for reasons including both danger to civilians and changing tactical requirements, the non-cluster unitary warhead XM31 missile is, in many cases, replacing even the M30.
Because of the weapon's broad area of effect, they have often been documented as striking both civilian and military objects in the target area. This characteristic of the weapon is particularly problematic for civilians when cluster munitions are used in or near populated areas and has been documented by research reports from groups such as Human Rights Watch, Landmine Action, Mines Action Canada and Handicap International. In some cases, like the Zagreb rocket attack, civilians were deliberately targeted by such weapons.
Even though cluster bombs are designed to explode prior to or on impact, there are always some individual submunitions that do not explode on impact. The US-made MLRS with M26 warhead and M77 submunitions are supposed to have a 5% dud rate but studies have shown that some have a much higher rate. The rate in acceptance tests prior to the Gulf War for this type ranged from 2% to a high of 23% for rockets cooled to −25 °F (−32 °C) before testing. The M483A1 DPICM artillery-delivered cluster bombs have a reported dud rate of 14%.
Given that each cluster bomb can contain hundreds of bomblets and be fired in volleys, even a small failure rate can lead each strike to leave behind hundreds or thousands of UXOs scattered randomly across the strike area. For example, after the 2006 Israel-Lebanon conflict, UN experts have estimated that as many as one million unexploded bomblets may contaminate the hundreds of cluster munition strike sites in Lebanon.
The US military is developing new cluster bombs that it claims could have a much lower (less than 1%) dud rate. Sensor-fused weapons that contain a limited number of submunitions that are capable of autonomously engaging armored targets may provide a viable, if costly, alternative to cluster munitions that will allow multiple target engagement with one shell or bomb while avoiding the civilian deaths and injuries consistently documented from the use of cluster munitions. Certain such weapons may be allowed under the recently adopted Convention on Cluster Munitions, provided they do not have the indiscriminate area effects or pose the unexploded ordnance risks of cluster munitions.
In the 1980s the Spanish firm Esperanza y Cia developed a 120mm caliber mortar bomb which contained 21 anti-armor submunitions. What made the 120mm "Espin" unique was the electrical impact fusing system which totally eliminated dangerous duds. The system operates on a capacitor in each submunition which charged by a wind generator in the nose of the projectile after being fired. If for what ever reason the electrical fuse fails to function on impact, approximately 5 minutes later the capacitor bleeds out, therefore neutralizing the submunition's electronic fuse system. Later a similar mortar round was offered in the 81mm caliber and equipped some Spanish Marine units. But on signing the Wellington Declaration on Cluster Munitions, Spain withdrew both the 81mm and 120mm "Espin" rounds from its military units.
Civilian deaths from unexploded cluster bomblets
- In Vietnam, people are still being killed as a result of cluster bombs and other objects left by the US and Vietnamese military forces. Estimates range up to 300 people killed annually by unexploded ordnance.
- Some 270 million cluster submunitions were dropped on Laos in the 1960s and 1970s; approximately one third of these submunitions failed to explode and continue to pose a threat today.
- During the 1999 NATO war against Yugoslavia U.S. and Britain dropped 1,400 cluster bombs in Kosovo. Within the first year after the end of the war more than 100 civilians died from unexploded British and American bombs. Unexploded cluster bomblets caused more civilian deaths than landmines.
- Israel used cluster bombs in Lebanon in 1978 and in the 1980s. Those weapons used more than two decades ago by Israel continue to affect Lebanon. During the 2006 war in Lebanon, Israel fired large numbers of cluster bombs in Lebanon, containing an estimated more than 4 million cluster submunitions. In the first month following the ceasefire, unexploded cluster munitions killed or injured an average of 3-4 people per day.
Areas with significant unexploded cluster bomb submunitions
- Indochina, especially in Laos and central Vietnam's former demilitarized zone.
- Nagorno Karabakh Republic
- Western Sahara