CANBERRA, Australia. -- For nearly a century, military doctrine was anchored by a fundamental truth: whoever controls the skies controls the battlefield. Today, the air is no longer the ultimate high ground—Space is.
During a visit to Australia to reinforce the critical alliance between U.S. and Australian military forces, Lt. Gen. Gregory Gagnon, commander of the U.S. Space Force Combat Forces Command, delivered a blunt assessment of the modern security environment.
He warned that space has unequivocally become a warfighting domain due to adversarial aggression from the People's Republic of China (PRC) and Russia, but emphasized that the U.S.-Australian collaboration offers a unique geographic and operational edge that our adversaries cannot replicate.
"We’re at another dynamic point in the history of warfare where the air is no longer the high ground. Space is the high ground," Lt. Gen. Gagnon stated. He noted that by leveraging the combined capabilities and prime geographic positioning of both nations, the Joint Force can "see where the adversary is" and maintain secure communications over vast distances—capabilities that are now foundational to the allied way of warfare.
China's Orbital Expansion
In 2013, China operated roughly a few dozen satellites. Today, that number has skyrocketed to approximately 1,400. Crucially, about half of these are remote sensing satellites focused squarely on the Indo-Pacific region.
The PLA uses this dense orbital architecture to track U.S. and allied naval and ground forces in real-time, feeding that targeting data directly to what is arguably the world's most formidable arsenal of long-range missiles.
"They are not moving out slowly. They are moving out like a world-class sprinter, and they are making gains," Gagnon said, noting that the PLA's space force is currently three times the size of America's.
The transformation of space into a battlefield is evidenced by aggressive physical developments. The PLA has developed, tested, and deployed an array of counter-space weapons, including ground-based missiles capable of destroying satellites—first demonstrated in 2007—and ground-based lasers designed to blind orbital sensors.
Russia, similarly, has demonstrated aggressive behavior in orbit, launching prototype weapons and actively maneuvering their satellites into threatening proximity to U.S. assets.
"They have built the weapons to attack us in space. They have practiced using those weapons to attack us in space," Gagnon noted. "They didn't do that just because they had nothing else to do."
Cooperative Readiness
Reliance on purely defensive strategies is no longer viable for the U.S. Joint Force and its allies. Securing this new high ground requires unprecedented cooperation. Space control is essential for allied prosperity and multi-domain operations. A cornerstone of this collective defense is Space Domain Awareness (SDA), which Gagnon identified as one of Australia’s most vital contributions.
Australia’s location in the Southern Hemisphere provides "prime real estate" for monitoring geospatial and low-Earth orbits. "Here in Australia, there is a high-powered telescope that is used to sense what's in space, and it's not used to look at stars. It's used to look at satellites," Gagnon remarked.
This geographic positioning is a massive strategic multiplier. "Part of the great strength of the United States Space Force is our partnership with Great Britain and Australia, because between the three of us, it gives us a geographic advantage that our adversaries do not enjoy," Gagnon explained. The dispersion of these three nations allows the alliance to maintain almost continuous, unbroken surveillance of Space.
The U.S. and Australia are further deepening their technical integration through shared architecture, including joint operations for missile warning, the Wideband Global SATCOM constellation, and discussions surrounding new proliferated Low Earth Orbit constellations. Crucially, this interoperability extends to human capital. Australian, Canadian, and British exchange officers are deeply integrated directly inside U.S. Space Force units to build shared proficiency—exemplified by the fact that the U.S. Space Force's combat forces operations officer is a Canadian general.
To maintain peace through deterrence, the alliance must be capable of offensive action. If conflict breaks out, the U.S. and its partners must be prepared to actively dismantle an adversaries’ space-based kill web.
"We are stronger together," Gagnon concluded. "One thing that gives strength is our ability to collectively defend ourselves, to expand those countries that are willing to defend freedom and protect their homelands together."