President Trump first announced his plans for increasing U.S. military capabilities in space in 2018. In August 2019, his administration created the United States Space Command. With the passage in December 2019 of the 2020 National Defense Authorization Act, the United States established the United States Space Force as a new branch of the armed forces. These developments do not directly implicate international law, but they reflect a growing divergence between the U.S. approach to space and that taken by the UN General Assembly.
In June 2018, Trump publicly announced his intention to establish “‘American dominance in space’” through the creation of a Space Force.Footnote 1 His announcement came after the release of the “Worldwide Threat Assessment of the US Intelligence Community,” which warned of China and Russia's capacity to “offset any perceived US military advantage derived from military, civil, or commercial space systems” through their antisatellite weapons, should the United States engage in military confrontation with the two countries.Footnote 2 A year later, on August 29, 2019, the Pentagon established the U.S. Space Command as a new geographic combatant command.Footnote 3 The U.S. Space Command is authorized to employ assigned forces from the various military service branches to achieve its mission “to deter aggression and conflict, defend U.S. and allied freedom of action, deliver space combat power for the Joint/Combined force, and develop joint warfighters to advance U.S. and allied interests in, from, and through the space domain.”Footnote 4
During the preparations for the negotiations between the White House and Congress over the 2020 National Defense Authorization Act (2020 NDAA), Trump reportedly instructed White House negotiators to make the creation of the Space Force their most important priority.Footnote 5 As a military service branch focused on space, the Space Force would complement the mission-focused Space Command. To secure Democratic support for the creation of the Space Force, the White House conceded to the inclusion of a provision for twelve-week paid parental leave for civilian federal employees.Footnote 6 Trump signed the 2020 NDAA into law on December 20, 2019,Footnote 7 thus establishing the United States Space Force (USSF) within the Department of the Air Force.Footnote 8
The USSF is headquartered in the Pentagon and is the sixth branch of the armed forces.Footnote 9 According to the USSF's mission statement:
The USSF is a military service that organizes, trains, and equips space forces in order to protect U.S. and allied interests in space and to provide space capabilities to the joint force. USSF responsibilities include developing military professionals, acquiring military space systems, maturing the military doctrine for space power, and organizing space forces to present to [the] Combatant Commands.Footnote 10
As the USSF is situated within the Department of the Air Force, the secretary of the air force—overseen by the secretary of defense—is responsible for the USSF.Footnote 11 In turn, the chief of space operations, a four-star general and a full member of the Joint Chiefs of Staff, serves as the “principal uniformed advisor to the Secretary of the Air Force on Space Force activities.”Footnote 12
The United States is party to the Outer Space Treaty, which obligates states to “carry on activities in the exploration and use of outer space … in accordance with international law, including the Charter of the United Nations, in the interest of maintaining international peace and security.”Footnote 13 The treaty bars the “place[ment] in orbit around the earth [of] any objects carrying nuclear weapons or any other kinds of weapons of mass destruction” and limits the use of the “moon and other celestial bodies” to “exclusively … peaceful purposes.”Footnote 14
While the creation of the U.S. Space Command and the USSF does not directly implicate international law, it does raise questions about future U.S. activities in space and about the compatibility of these activities with international law. General Mark A. Milley, chairman of the Joint Chiefs of Staff, stated that space is of strategic military importance because it supplements combat operations on Earth, but it is also a “warfighting domain in and of itself.”Footnote 15 The mission of the U.S. Space Command reflects Milley's attitude—one of the U.S. Space Command's focus areas is that it “will improve the development of joint space operations forces and capabilities to enhance space warfighting readiness and lethality while accelerating the integration of space capabilities into other warfighting forces.”Footnote 16 Similarly, the duties of the USSF are to “deter aggression in, from, and to space” and “conduct space operations.”Footnote 17 These developments contrast with recent actions taken at the United Nations, where five resolutions were adopted at the seventy-fourth session of the General Assembly addressing the issue of the prevention of an outer space arms race.Footnote 18