https://www.microwavejournal.com/articles/38247-leo-constellations-the-new-military-frontier
Traditionally, aerospace and defense organizations used geostationary orbit (GEO) and higher-orbit satellites, very complex systems with longer development and production cycles. While low Earth orbit (LEO) constellations were considered, the benefits of numerous small satellites in multiple orbits connected as a single network were not proven and the challenges significant. However, once development efforts began to overcome size, weight, power and cost constraints, LEOs started a new space race.
Military and government organizations are increasingly eying LEO satellites for military applications. In the U.S., for example, the president requested a $24.5 billion budget for the U.S. Space Force and Space Development Agency for fiscal year 2023. However, the viability of LEOs for aerospace and defense will depend on performance assurance throughout development, launch and the mission. This task has two challenges: proving capabilities for military applications and verifying performance at higher frequencies and wider bandwidths.