Vice President Mike Pence announced the presidential decision on Tuesday during an appearance at Kennedy Space Center, Florida, along with Air Force Secretary Heather Wilson.

WASHINGTON — President Trump on Tuesday directed the Department of Defense to establish a U.S. Space Command as a unified combatant command.

Vice President Mike Pence announced the presidential decision on Tuesday during an appearance at Kennedy Space Center, Florida, along with Air Force Secretary Heather Wilson.

The president in a Dec. 18 memo instructed the Pentagon to establish a United States Space Command as a “functional Unified Combatant Command.” He also directed the Secretary of Defense to recommend officers for nomination and Senate confirmation as Commander and Deputy Commander of the new command.

The Defense Department currently has 10 combatant commands, each with a geographic or functional mission. U.S. Space Command would become the 11th.

During a media call on Tuesday following the announcement, Wilson said having a four-star combatant command for space is a “tremendous step forward” as the Pentagon turns more attention to space as a domain of warfare.

After the news of Trump’s memo broke on Tuesday morning, speculation swirled on social media that U.S. Space Command would replace U.S. Air Force Space Command. Wilson said both organizations fulfill different missions. U.S. Space Command will become the military’s unified command for space. Air Force Space Command, meanwhile, will be reorganized under the president’s plan to stand up a new military branch for space.

Air Force Lt. Gen. John Thompson, commander of the Space and Missile Systems Center, elaborated further during the call. “The whole point behind a combatant command is to do our war fighting missions whereas the point behind Air Force Space Command is to provide the resources necessary to organize, train and equip, and provide forces to that combatant command.”

The United States had a Space Command from 1985 until 2002. It was disestablished and its functions were absorbed by U.S. Strategic Command during the George W. Bush administration to free up resources to create U.S. Northern Command to oversee homeland defense.

Wilson called this an opportune time to bring back U.S. Space Command because of rising space security threats. “It was unanimously supported by all the Joint Chiefs of Staff,” she said. “That is military advice that is worth listening to.” DoD organized a number of tabletop exercises and strategy sessions that helped inform the plans to stand up the new command. “We are shifting to a war fighting culture at the explicit recognition that it is a war fighting domain,” Wilson added. “Adversaries are developing capabilities to deny us the use of space in crisis or war. The creation of a unified command puts focus on the ability to protect our assets on orbit and prevail if called upon.”

Deputy Defense Secretary Patrick Shanahan — who is overseeing the Pentagon’s efforts to establish a Space Force as a new military branch — explained on Twitter that Space Command should not be confused with Space Force. “The Space Force will serve as a force provider for personnel, assets, and capabilities supporting space operations while Space Command will serve as the operational command that will employ space capabilities and lead space operations.”

Once both organizations are up and running, Shanahan added, the differences between Space Force and U.S. Space Command will “largely parallel those of the other five military services and four functional combatant commands.”

As work begins to establish a new combatant command, the Pentagon in parallel is developing a legislative proposal to stand up a Space Force as a sixth U.S. military service.

“It is urgent that we address space as a warfighting domain and this combatant command is a critical step in that direction,” Shanahan added. “U.S. Space Command will allow us to accelerate our space capabilities to defend our national interests and deter our adversaries.”

As to who might be on the short list to run U.S. Space Command, several sources said the obvious candidates would be Air Force Space Commander Gen. John Raymond and Vice Commander Lt. Gen. D.T. Thompson.