Between 1967 and 1984 five space-specific treaties entered into force.
The first and most comprehensive of those, the 1967 Outer Space Treaty, refers to the use and exploration of outer space for ‘peaceful purposes’. However, the instruments do not expressly address the initiation and conduct of hostilities involving outer space, and little State practice exists on the subject.
The law governing the resort to force set forth in the UN Charter and the law of armed conflict have long been accepted by States as applicable to operations involving outer space. Yet, the manner in which these bodies of law should be interpreted in the context of outer space has not been comprehensively examined. This resulting lack of normative clarity presents the risk of State or non-State actors taking action involving outer space that might be misunderstood by others, or even characterised as unlawful. It also allows States that might wish to conduct hostile space operations to do so in a zone of uncertainty, that complicates responses by other States. Therefore, it is essential that space actors not only acknowledge that there is a rules-based order that applies to outer space, even in periods of tension and hostilities, but also that they have an understanding of when and how those rules apply.
Non-governmental efforts can help clarify the application of the law governing resort to force and law of armed conflict to new domains and means and methods of armed conflict. The success of the San Remo Manual on International Law Applicable to Armed Conflict at Sea, the Harvard Manual on International Law Applicable to Air and Missile Warfare, and the Tallinn Manual on International Law Applicable to Cyber Operations (versions 1.0 and 2.0) demonstrate how international experts and associated engagement with governments can offer an authoritative and clear articulation of international law in new domains for government legal advisers, decision-makers, and operators. The Woomera Manual aims to replicate - with respect to outer space - the successes of these earlier manuals.