President Trump will sign Space Policy Directive-4 (SPD-4) tomorrow at 2:00 pm ET along with Vice President Mike Pence, who chairs the White House National Space Council. The directive’s focus is creation of the Space Force as part of the U.S. Air Force as a first step towards creating a separate military department. Congress must approve the proposal.

The idea of reorganizing the Air Force to better manage and execute national security space programs was initially pushed by the House Armed Services Committee (HASC). The House-passed version of the FY2018 NDAA included a requirement to establish a Space Corps within the Air Force analogous to the Marine Corps within the Department of the Navy. The Senate Armed Services Committee did not agree, however, and the final version of that bill called for a study instead. Congress required that the study be completed by August 1, 2018 and led by the Deputy Secretary of Defense (SecDef). Patrick Shanahan was Deputy SecDef at the time. He is now Acting SecDef.

Trump first mentioned a Space Force in March 2018, but his most detailed statement came in June at the signing of SPD-3 where he made it clear that he did not want an entity subordinate to the Air Force. Instead he called for a sixth military department “separate but equal” to the others.

In August, Pence released the “Shanahan report” required by the FY2018 NDAA at a Pentagon press conference. Shanahan and a group of high level DOD officials including Air Force Secretary Heather Wilson and Under Secretary of Defense for Research and Engineering Mike Griffin have been figuring out the details to put into a legislative proposal to Congress ever since.

The idea of a new military department and its attendant cost and bureaucracy has not been warmly received by either Republicans or Democrats in Congress. Thus it is not surprising that SPD-4 is closer to what HASC proposed rather than what Trump wanted, although it keeps Trump’s Space Force name and is characterized as a step towards a separate department.

The key features of SPD-4 are for the SecDef to develop a legislative proposal that would do the following:

Establish a Space Force as a sixth military department of the Armed Forces within the U.S. Air Force as a first step toward a future, separate military department.

Establish a Chief of Staff of the Space Force within the Air Force who will be a member of the Joint Chiefs of Staff.

Create a civilian Under Secretary of the Air Force for Space to be appointed by the President with the advice and consent of the Senate.

Consolidate existing forces and authorities for military space activities in order to minimize duplication of effort and eliminate bureaucratic inefficiencies.

Include military and civilian personnel conducting and directly supporting space operations from all military departments and DOD Armed Forces; assume responsibilities for all major military space acquisition programs; and create appropriate career tracks across all relevant specialties.

military and civilian personnel conducting and directly supporting space operations from all military departments and DOD Armed Forces; assume responsibilities for all major military space acquisition programs; and create appropriate career tracks across all relevant specialties. Exclude NASA, NOAA, NRO or other non-military space organizations or missions of the U.S. government.

NASA, NOAA, NRO or other non-military space organizations or missions of the U.S. government. Require the Space Force to organize, train and equip forces to provide for U.S. freedom of operation in the space domain; provide independent military options for joint and national leadership; and enable the lethality and effectiveness of the joint force.

The FY2020 budget request will include a budget for the Space Force.

The directive also requires the SecDef and the Director of National Intelligence to report to the President within 180 days on how to create and enhance mechanisms for collaboration across the two communities.

The SecDef is further directed to propose to the President relevant operational authority changes and to conduct periodic reviews to determine the appropriate time to propose legislation to establish a separate military department.

Trump has already begun the process to create a unified combatant command, U.S. Space Command. SPD-4 lays out the responsibilities of the commander of that new command — to lead space warfighting through global space operations that may occur in the space domain, the terrestrial domains, or through the electromagnetic spectrum.