The event in Colorado Springs was attended by representatives from Britain, Australia, Canada and New Zealand.
Also taking part were various US government agencies, including the defence threat reduction agency and Nasa.
The military news site Defence One said: “While Whiting and US Space Command did not disclose the wargame’s findings, open-source reports have detailed the widespread devastation such a weapon would cause to all satellites in orbit.”
Chief Master Sgt Jacob Simmons of the US Space Command told an earlier wargame session: “Space is no longer a supporting supplement…it is a central system woven into the web of our modern life, from markets to medicine, from agriculture to aviation, from navigation to notification, we are all synchronised with space.”
He added: “If and when space is struck down, all of society is struck down.”
The wargames come amid a growing scramble for dominance or control of space involving the US, Russia and China.
In May 2024, the US said it had detected what it believed was a new device – dubbed Cosmos 2576 – that had been launched from western Russia.
“We have observed nominal activity and assess it is likely a counter-space weapon presumably capable of attacking other satellites in low Earth orbit,” said a spokesperson for the US Space Command.
“Russia deployed this new counter-space weapon into the same orbit as a US government satellite.”