President Trump wants to create the U.S. Space Force as the sixth military branch.

But that’s not Trump’s call to make, according to the Congressional Research Service. Only Congress has the authority to create a new branch of the military, according to a new CRS report.

“The constitutional framework appears to contemplate that the role of establishing, organizing, regulating, and providing resources for the Armed Forces belongs to Congress, while the President is in charge of commanding the forces Congress has established using the funds Congress has provided,” CRS concluded.

In a rather legalistic analysis, CRS examined the various legislative options for establishing the Space Force:

Make Space Force part of an existing branch. “The President could direct the service secretaries to develop new units or restructure existing units to provide greater capability and capacity to conduct space operations,” CRS said. Congress can also mandate by enacting statutes, or using its appropriations and oversight powers to encourage the White House to choose this option.

Make Space Force like the Marine Corps. “Congress could establish a separate military service focused on space operations within one of the existing military departments, in a manner similar to the way the Marine Corps exists within the Department of the Navy,” CRS noted.

Create a new Space Combatant Command. “The President could direct the establishment of a space-oriented COCOM, or a subordinate unified combatant command under an existing COCOM (similar to the subordination of U.S. Forces Korea to U.S. Indo-Pacific Command). Alternatively, Congress could require the establishment of a space-oriented COCOM in law, perhaps with special authorities, as it did with the establishment of Special Operations Command and Cyber Command.” Already, the Fiscal Year 2019 National Defense Authorization Act provides for the establishment of a space force as a subordinate unified command, to be known as U.S. Space Command, under the control of U.S. Strategic Command.

Create a new military department. “Congress could choose to establish a new military department with a new military service focused on space operations,” said CRS. The report pointed to Congress’s 1947 National Security Act, which established the U.S. Air Force—which had been a part of the U.S. Army—as an independent Department of the Air Force.

The CRS analysis highlighted the inherent conflict between Congress's control of the purse strings and the President's control of the armed forces as commander-in-chief. In a sign of just how complicated the issue is, CRS noted that the Constitution refers to Congressional authority over the Army, Navy and militia (reserves).

So does space fall under these categories? "The President's commander-in-chief authority is similarly limited to the Army and Navy and activated reserve components," CRS concluded. "However, it is unclear whether a new Space Force would actually carry out functions in space or that its functions would be any different from those related to space operations already carried out by the various services."

CRS also takes care to point out that while the Constitution doesn’t mention an air force—not likely in 1789—no one has questioned the authority of Congress or the President over the U.S. Air Force.

Budgetary and personnel issues will also complicate the creation of Space Force. Nonetheless, CRS believes there is ample precedent for military restructuring, such as the creation of the U.S. Air Force and Cyber Command, or the 1986 Goldwater-Nichols Act, which revamped the U.S. military command structure. But this legislation “took varying amounts of time and hearings to establish (e.g., the creation of the Air Force took three years of hearings), and most provide varying degrees of lessons learned, both good and bad.”

Michael Peck is a contributing writer for the National Interest. He can be found on Twitter and Facebook.

Image: Reuters