International partnerships and cooperation among allies are key components of the United States' strategy to deter conflict and reinforce safety and stability in space.
Those partnerships were on full display this month as space operators from 25 partner nations gathered to participate in Global Sentinel, U.S. Space Command's marquee exercise focused on security cooperation and operational collaboration in the frontier warfare domain.
Throughout the two-week exercise held at Vandenberg Space Force Base in California, each participating nation organized into Regional Space Operations Centers aligned to maintain command and control across an array of space sensors.
The scenarios presented during the exercise, which concluded last week, were designed to improve space situational awareness and strengthen interoperability among the participating nations.
Italian Air Force Col. Dario Tarantino said improving space situational awareness and maximizing interoperability across partner nations is critical for maintaining safety and security in space.
"One of the issues with the space domain is complexity," he said. "It's a complex domain – it's difficult to understand sometimes."
He said potential threats in space can often be ambiguous and difficult to understand if those threats are intentional or unintentional.
"That is why we need to increase our sharing of our [tactics, techniques and procedures] and our sharing of operations in terms of interoperability to increase our level of comprehension of the complex and ambiguous domain," Tarantino said.
In addition to the U.S. and Italy, this year's participants included Australia, Belgium, Brazil, Canada, Colombia, Finland, France, Germany, Israel, Japan, Netherlands, Norway, New Zealand, Peru, Poland, Portugal, Republic of Korea, Romania, Spain, Sweden, Thailand, Ukraine and the United Kingdom.
India and Mexico also attended the last two days of the exercise as observers along with representatives from NATO.
Global Sentinel is the only exercise of its kind that brings together multinational partners in a single venue to collaborate on issues focused on space security.
It represents the recognition among participants that alliances and partnerships are key to ensuring that their shared interests in space remain protected.
Dr. John F. Plumb, assistant secretary of defense for space policy, has emphasized the critical role of cooperation among allies as global competitors increasingly look to space as the next frontier of warfare.
In outlining the U.S. approach for maintaining its edge in space last month, Plumb emphasized that these partnerships are key to building "an asymmetric advantage and force multiplier that neither China nor Russia could ever hope to match."
Global Sentinel, which began in 2014 as a space situational awareness tabletop event among seven nations, has grown in both size and complexity in recent years.
A total of 246 participants, including 177 international partners, were involved in this year's exercise.
"From a purely numbers perspective, the size of the game has grown significantly," said Global Sentinel planner Air Force Lt. Col. Patrick Mitchell.
Mitchell noted the number of space sensors used and the complexity of the exercise has grown significantly in recent years. This year, participants managed 97 sensors used to maintain space situational awareness, up from 50 sensors at play in 2022.
"Those sensors were modeled in the simulation," Mitchell said. "They are [using] real world sensors, and just the volume of sensors is so much higher than it was in previous iterations."
Mitchell stressed that working with international partners to address complex scenarios yields tangible results.
Nations involved in the exercise often face real world events requiring collaboration across partners, and Mitchell said the links built during Global Sentinel are critical to that interoperability.
"We've established that lexicon, the ability to talk to each other, and then put that to work in the real world for the benefit of space situational awareness," he said.
In that respect, Mitchell said Global Sentinel is not just a simulation.
"There are tangible benefits that do come out of this event," he said.
Other participants echoed Mitchell in noting the benefits of those connections built during the exercise.
"This is a great opportunity for so many people to gather in the same place and spend two weeks together," said Japan Air Self Defense Force Col. Kimitoshi Sugiyama.
He said participants come away from the exercise with a better understanding of their international partners' procedures and develop skills that will immediately translate into the real world.
"We have a chance to [build] human connections," he said. "This is a very important asset."