Warfare in Space

Getting your Trinity Audio player ready...


With the emergence of space technology, there is an increasing desire on the part of States with spacefaring capacity to pursue the domain for military purposes. The first instance of an armed conflict which used space was the Gulf War of 1991 where the domain was used to collect information and to improve on the ground coordination. Since then, countries like China, Russia, India and the United States are actively pursuing military uses of space and look at the domain as essential to their security and as a means for deterrence and defence against attacks. This article explores the history of space warfare, the use of space as a domain for armed conflict (with a focus on the U.S., Russia, China, and India), space laws, regulation of space war through the lens of IHL and the issues with its application.

History of Space Warfare

The Cold War between the world superpowers – the United States of America and the Soviet Union – marked the beginning of an era in which they were preoccupied with proving their superiority over each other in all fields; technology, military firepower, politics and the economy. Due to technological progress, space exploration served as another arena in which this was possible and this led to the space race. In 1957, Russia launched Sputnik-I (an artificial satellite) which posed a threat to the USA. The USA feared it could deliver a nuclear warhead into U.S. airspace. The U.S. army launched its first satellite ‘Explorer I’ the year after, and then established a federal agency for space exploration called the National Aeronautics and Space Administration (NASA). In 1959, the USA launched a strategic defensive weapon called the intercontinental ballistic missile (ICBM). ICBM was originally the first space weapon which transformed the strategic nature of space warfare. The U.S. Air Force then started national security-oriented space programs to exploit the military potential of space. From 1960-72, it operated a program code-named ‘CORONA’ in collaboration with the Central Intelligence Agency (CIA) and the National Reconnaissance Office (NRO). CORONA gathered intelligence on the Soviet Union and its allies by using satellites. The satellites operated by NRO had the support of the U.S. Air Force’s missile warning satellites which provided the first line of defense against any strikes. The Soviets imitated the same space strategy and used satellites to track the nuclear movement in the USA. With successful Apollo missions, the launch of America’s reusable space shuttle, and the beginning of the Strategic Defense Initiative – the USA invested heavily in space technology. The Soviets tried to keep up by modernizing their ICBM and developing their first anti-satellite weapon – however, it feared America’s rapid space developments and this was one of the reasons it agreed to the Reykjavik summit in 1986. This summit marked an end to the Cold War.1‘The Space Race’ (21 February 2021) <https://www.history.com/topics/cold-war/space-race> accessed 13 June 2022; < https://www.nps.gov/articles/series.htm?id=09AF828C-1DD8-B71B-0B7EF976E874E182> accessed 13 June 2022; Captain John Shaw, ‘The Influence of Space Power upon History (1944-1998) <https://www.airuniversity.af.edu/Portals/10/ASPJ/journals/Chronicles/shaw.pdf> accessed 15 June 2022

Use of Space as a Domain for Armed Conflict

The first use of space weapons took place in Operation Desert Storm when the Gulf war broke out in 1991. The use of satellite communications played a huge role in coordination as the Defense Meteorological Satellite Program (DMSP) assisted in collecting weather data and aided in the movement of troops. The Global Positioning System (GPS) was used by the military, navy and air force to plan their attack and defense. Defense support program (DSP) satellites also provided Israel and Saudi Arabia with missile warning data.2Robert S. Dudney, ‘Space Power in the Gulf’ (Airforcemag, 1 June 2003) <https://www.airforcemag.com/article/0603edit/> accessed 15 June 2022; Steven J. Bruger, ‘Not Ready for the First Space War: What About the Second?’ (1995) Naval War College Review 48 (1) <https://www.jstor.org/stable/44642734> accessed 17 June 2022 Similarly, during the Vietnam War, air drones were used for aerial photo-reconnaissance to support the U.S. military. The DMSP military weather satellites provided weather images and tactical weather information to the commander-in-chiefs. The troops relied heavily on the data provided by DMSP to conduct combat operations.3David N. Spires, ‘Beyond Horizons’ (1998) <https://www.airuniversity.af.edu/Portals/10/AUPress/Books/B_0063_SPIRES_BRADLEY_STURDEVANT_ECKERT_BEYOND_HORIZONS.pdf> accessed at 17 June 2022

Currently, countries like China, Russia, India and the United States are actively pursuing military uses of space. In 2005 and 2007, China carried out anti-satellite destruction tests. The test carried out in 2007 was met with international criticism especially from the U.S. as it created a large amount of space debris.4Dafna Linzer, Marc Kaufman, ‘China criticized for Anti-Satellite missile test destruction of an aging satellite illustrates vulnerability of U.S. space assets’ (Washington Post, 19 January 2007) <https://www.washingtonpost.com/archive/politics/2007/01/19/china-criticized-for-anti-satellite-missile-test-span-classbankheaddestruction-of-an-aging-satellite-illustrates-vulnerability-of-us-space-assetsspan/ae3462c4-c2d9-422b-bc17-dc040458fe64/> accessed 18 June 2022 In 2018, a National Space Strategy and National Defense Strategy was issued by the U.S. which recognised that its adversaries including China and Russia have turned space into a warfighting domain. India is also a participant in this space arms race as it conducted an anti-satellite weapons test in March 2019 which resulted in space debris. The Indian Defense Space Research Organization (DSRO) is engaged in developing space arms and the Indian Defence Ministry made it evident that space warfare is a priority area till 2025.5‘Militarization of Space by India’ (The Nation, 21 March 2022) <https://nation.com.pk/2022/03/21/militarization-of-space-by-india/#:~:text=India’s%20Defense%20Space%20Research%20Organisation,operationalization%20of%20space%20warfare%20dimension.> accessed at 20 June 2022 The North Atlantic Treaty Organization (NATO) recognized space as an operational domain for military operations in 2019. The NATO Allies adopted NATO’s Space Policy as essential to their security and for deterrence and defense against attacks from their adversaries.6‘NATO’s approach to space’ (2 December 2021) <https://www.nato.int/cps/en/natohq/topics_175419.htm> accessed at 20 June 2022 As a result, the militarisation of space and the use of space as a domain in which and from which warfare will be conducted seems to be an inevitability.

The Law Applicable in Space

The United Nations is the principal organization for cooperation in outer space and for formulating international laws on the use of outer space. The developments which took place under the ambit of UN includes:

  • The general multilateral treaties are: Outer Space Treaty (1967); Agreement on the Rescue of Astronauts, the Return of Astronauts and the Return of Objects Launched into Outer Space (1968); Convention on International Liability for Damage Caused by Space Objects (1972); Convention on Registration of Objects Launched into Outer Space (1976); Moon Treaty (1979); and Agreement Governing the Activities of States on the Moon and Other Celestial Bodies (1984).
  • United Nations General Assembly (UNGA) resolutions namely the Declaration of Legal Principles Governing the Activities of States in the Exploration and Use of Outer Space (1963); Principles Governing the Use by States of Artificial Earth Satellites for International Direct Television Broadcasting (1982); Principles Relating to Remote Sensing of the Earth from Outer Space (1986); Principles Relevant to the Use of Nuclear Power Sources in Outer Space (1992); Declaration on International Cooperation in the Exploration and Use of Outer Space for the Benefit and in the Interest of All States, Taking into Particular Account the Needs of Developing Countries (1996).

Limits on the military use of outer space were laid down in treaties. The Outer Space Treaty (OST) also known as the Principles Treaty7Outer Space Treaty (1967) <https://media.nti.org/documents/outer_space_treaty.pdf> accessed 21 June 2022 is considered the foundational legal basis for the peaceful uses of outer space. According to the OST (1968), the Moon and other celestial bodies should be used for peaceful purposes. The establishment of military bases, installations, and fortifications; the testing of any type of weapons; and the conduct of military maneuvers on celestial bodies are forbidden – therefore, it outlaws the militarization of space. Military personnel can conduct scientific research or use space for any other peaceful purposes and the use of any equipment or facility necessary for peaceful exploration of the Moon and other celestial bodies is also allowed. Under the Liability Convention (1972),8UNOOSA, ‘Convention on international liability for damage caused by space objects’ <https://www.unoosa.org/oosa/en/ourwork/spacelaw/treaties/introliability-convention.html#:~:text=Elaborating%20on%20Article%207%20of,to%20its%20faults%20in%20space.> accessed at 21 June 2022 a State launching any space object which causes damage to the surface of the Earth or to aircraft or any damage in space is liable to pay compensation.

International Humanitarian Law in Space

IHL applies unequivocally to all military operations that satisfy the rules pertaining to an international or non-international armed conflict. Article 3 of the OST mandates that international law applies to activities conducted in outer space, and since IHL forms part of that international law, it is applicable. The International Court of Justice in its Advisory Opinion also stated that IHL applies to all forms and kinds of warfare and weapons.9ICJ, Legality of the threat or use of nuclear weapons’ (8 July 1996) <https://www.icrc.org/en/doc/resources/documents/article/other/57jnfm.htm> accessed 22 June 2022

According to the International Committee of the Red Cross (ICRC), the use of weapons in outer space could cause harm to civilian life.10ICRC, ‘The Potential Human Cost of the Use of Weapons in Outer Space and the Protection Afforded by International Humanitarian Law’ (8 April 2021) <https://www.icrc.org/en/document/potential-human-cost-outer-space-weaponization-ihl-protection> accessed 21 June 2022 The question arises: how can IHL regulate war in space? IHL puts restrictions on the use of superfluous weapons and it mandates that the means and methods of warfare should not be indiscriminate and should not cause superfluous injuries or unnecessary suffering.11ICRC, ‘How does IHL regulate the means and methods of warfare?’ (13 August 2017) <https://blogs.icrc.org/ilot/2017/08/13/ihl-regulate-means-methods-warfare/#:~:text=IHL%20prohibits%20the%20use%20of,been%20derived%20from%20these%20principles.> accessed 21 June 2022 It also prohibits direct attacks against civilians or civilian objects according to which civilian space objects shall be protected at all costs.12Article 48 of Additional Protocol I Only the objects used with an intent to further a military agenda should be targeted.13Article 52 (2) of Additional Protocol I Therefore, no space object should be attacked unless it is proven that it was being used as a military objective. Since the principle of distinction prohibits all sorts of indiscriminate attacks,14Article 51 (4) of Additional Protocol I civilian space objects and civilians should not be targeted. All attacks disproportionate in nature are prohibited15Article 51 5(b) of Additional Protocol I, therefore, before attacking, the foreseeable direct and indirect incidental harm to civilians or civilian objects in outer space and on Earth should be determined. The objects crucial to the survival of the civilian population should be protected16Article 14 of Additional Protocol II, hence, space objects indispensable to the survival of civilians should not be attacked or destroyed. When carrying out military operations in space, the status of protected persons such as that of medical personnel should remain intact, as medical units and services are protected under IHL.17Article 12 of Additional Protocol I; Article 11 of Additional Protocol II IHL also creates an obligation on the belligerent parties to protect the natural environment18Article 55 of Additional Protocol I, therefore, the space debris issue needs to be addressed as it could damage other space objects that support civilian services.

There are some legal challenges when it comes to applying IHL to space warfare. It is hard to distinguish civilian from military objectives. The astronauts operating military spacecraft in a space war would be considered combatants or military objectives. In conventional armed conflicts, combatants are distinguished by their military uniforms but in space where such combatants are inside high speed spacecraft it is unlikely that such a visible determination would be feasible. Similarly, as IHL prohibits attacking civilian objects, it is difficult to identify the nature and purpose of objects in ‘dual use’ For example, the global navigation satellite systems such as GPS is used in civilian transport systems and also helps in maneuvering military objects. The attack of military satellites would be justified but if an ordinary navigation satellite provides services to armed forces then before an attack is launched, it should be ensured that the nature of the satellite was to offer a definite military advantage, and that the injury or death to civilians is proportionate to this advantage. As satellites are increasingly used for civilian needs it becomes all the harder to determine which ones are military and, if dual-use, gauging the interconnected nature of the effects on civilian life. As there is little state practice in space yet, these are issues that the international community will continue to grapple with as we see the increasing militarisation of space.


The first space war took place in 1991 and since then States have been ramping up their capabilities in space in order to use it to their military advantage. Spacefaring states are showing this capacity by conducting anti-satellite tests. However, this capability increases the likelihood that wars may be fought from and in space in the future. While we may not have had an outright ‘space war’ yet, even the use of satellites for on-the-ground war coordination is a significant development. The treaties that regulate outer space acknowledge that IHL continues to apply in conflicts in space, however, there is little clarification as to how this would govern military satellites where combatants and civilians are not visible. Moreover, dual-use satellites are important for civilian life and the parameters of their targeting are not clearly defined given the potential knock-on effects of their destruction. As a result, it is necessary that State representatives, scholars, civil society members, and military commanders discuss and formulate the effective codification of these laws and their application to outer space similar to the Tallinn Manual’s guidance with respect to cyberspace. The Woomera Manual is a welcome endeavour in this regard and as it is due for completion in 2022, it promises to be a very useful addition clarifying how existing international law applies to military space operations.


The opinions expressed in the articles on the Diplomacy, Law & Policy (DLP) Forum are those of the authors. They do not purport to reflect the opinions or views of the DLP Forum, its editorial team, or its affiliated organizations. Moreover, the articles are based upon information the authors consider reliable, but neither the DLP Forum nor its affiliates warrant its completeness or accuracy, and it should not be relied upon as such.

The DLP Forum hereby disclaims any and all liability to any party for any direct, indirect, implied, punitive, special, incidental or other consequential damages arising directly or indirectly from any use of its content, which is provided as is, and without warranties.

The articles may contain links to other websites or content belonging to or originating from third parties or links to websites and features in banners or other advertising. Such external links are not investigated, monitored, or checked for accuracy, adequacy, validity, reliability, availability or completeness by us and we do not warrant, endorse, guarantee, or assume responsibility for the accuracy or reliability of this information.

Areesha Shahid

Areesha Shahid is a law student currently interning at the Research Society of International Law. She works as a youth advisory board member of Amnesty International and as secretary-general youth council at the Think Tank Pakistan. Miss Shahid has a keen interest in Public International Law, particularly in IHRL and IHL. She can be reached at her Linkedin.