Vice President Mike Pence and National Security Adviser John Bolton led a classified meeting Friday with top national security and military officials at the White House to simulate how to "deter and defeat" the "increasingly concerning threats" posed by U.S. adversaries in space, a White House official told Axios.

Why it matters: The meeting gives us a preview into who will be the leading voices on the president's Space Force, which hasn't been formally established yet.

Details: Participants included Commerce Secretary Wilbur Ross, Treasury Secretary Steve Mnuchin, DHS Secretary Kirstjen Nielsen, Deputy Secretary of Defense Patrick Shanahan, Under Secretary of State for Arms Control and International Security Affairs Andrea Thompson, as well as other senior civilian leaders.

Several senior military leaders including the Vice Chairman of the Joint Chiefs of Staff Gen. Paul Selva, Strategic Command Commander Gen. John Hyten, and European Command Commander Gen. Curtis Scaparrotti were also present.

Pence is the chairman of the National Space Council.

The White House would not share the specific threats that the group was simulating during the meeting, citing "the classified nature of the exercise."

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