At the December 2019 NATO Leaders’ Meeting in London, Allies declared space a fifth operational domain, alongside air, land, sea and cyberspace: “We have declared space an operational domain for NATO, recognising its importance in keeping us safe and tackling security challenges, while upholding international law.“
“Space support to operations includes all activities that provide capabilities through space in order to support NATO operations. Space is congested, contested and competitive. Freedom to act in the space domain and employ space capabilities is crucial to the outcome of conflicts.”
NATO Allied Joint Publication (AJP 3.3 (B) Allied Joint Doctrine for Air and Space Operations, Chpt. 5.1.1.
“Winning the battle in space may not lead directly to winning the war. But if you lose in space, you are guaranteed to lose the war.”