States have been increasing the use of satellites for military purposes, given their important strategic role to guarantee both national security and the good outcome of war operations. Although perceptions of threats vary considerably, there are at least three scenarios that require attention: hostile actions from space to space, from space to ground and from ground to space, as well as activities against ground infrastructures connected to space objects. Examples of such weaponization include the deployment of orbital or suborbital satellites designed to collide with or intercept other satellites; the use of ground-based direct-ascent anti-satellite (ASAT) missiles; the employment of electronic warfare measures, such as signal jamming; non-kinetic attacks (for instance, cyberattacks).
This situation, compounded by the dual nature of space activities, is part of a context in which the international legal framework has pitfalls that have long been the subject of extensive debate and attempts at legal regulation, including those initiated within the United Nations. The conventional rules governing States activities in outer space are contained in the five UN treaties adopted between 1967 and 1979. In particular, the 1967 Outer Space Treaty and 1979 Moon Agreement are the two legal instruments that contain specific provisions limiting the use of outer space for military purposes. The OST completes the 1963 Partial Test Ban Treaty (PTBT) which prohibits nuclear experiments in outer space.
Since 1981, the United Nations General Assembly has regularly addressed the risk of an arms race in outer space through what is known as the Prevention of an Arms Race in Outer Space (PAROS) initiative. Over time, the PAROS process has generated a wide debate on the topic which led to the adoption of UN resolutions, and negotiations of legal instruments. Among these there have been the Draft Treaty on Prevention of the Placement of Weapons in Outer Space (PPWT), proposed jointly by Russia and China, which seeks to ban all space weapons and restrict defensive systems; the European Union–led Draft International Code of Conduct for Outer Space Activities, a non-binding set of guidelines intended to enhance transparency, encourage best practices, and reduce the risk of misunderstandings. So far, the main initiative that led to a positive outcome was the establishment of a Group of Governmental Experts on Transparency and Confidence-Building Measures (TCBMs) in Outer Space. Established by the UN Secretary-General, the work of the Group of Governmental Experts on TCBMs led to agreement on the identification of TCBMs in space activities. The final report was approved by consensus by the General Assembly with Resolution 68/50 of 5 December 2013.
Although progress has been slow and often blocked by political disagreements, UN initiatives since 2017, including the newly establishment of two Open-Ended Working Groups, signal a renewed commitment to tackling the militarization of space. In January 2022, the United States announced a unilateral moratorium on direct-ascent ASAT missile tests, reaffirming a voluntary policy first articulated in 2008. Later that year, in November 2022, the UN General Assembly adopted Resolution 77/41 by a vote of 155 in favor, 9 against, and 9 abstentions; this resolution called on all states to support a moratorium on destructive ASAT tests. India, China, and Russia voted against the Resolution, whereas 37 other countries, including Italy (which issued its official statement in April 2023), endorsed the moratorium.
In April 2024, the United States and Japan jointly introduced draft resolution S/2024/302 to the United Nations Security Council with the aim of prioritizing space security on the Council’s agenda for the first time. Although the draft was supported by 65 Member States, it was ultimately vetoed by Russia, underscoring the persistent divisions over the topic of weaponisation in outer space.
Ongoing debates on preventing an arms race in space reveal divergences over several critical legal issues. PAROS continues to be widely debated at the international level with the aim of providing new impetus for the development of regulatory instruments to address the challenges posed by the weaponisation of space. It emphasizes the need for a more inclusive and coordinated approach with some countries, particularly Russia and China, favouring the negotiation of a binding treaty, namely the PPWT, and others preferring processes for the development of non-binding instruments containing principles of responsible behaviour as a preliminary step towards the conclusion of a binding treaty.
On these topics, read a contribution by Pierfrancesco Breccia at the following link!
