WASHINGTON — After President Trump told Marines in California that he believed the U.S. military should have a space force, there was confusion. Was he serious? Was it an off-the-cuff riff? And why would he endorse an idea adamantly opposed by his own Defense Department?

The president apparently was not joking.

"He is very interested in ensuring that the department is best organized and equipped to achieve our vital missions in space," Kenneth Rapuano, assistant secretary of defense for homeland defense and global security, told lawmakers on Thursday. [Related: Trump Says US May Need a Military 'Space Force']

Rapuano testified at a hearing of the House Armed Services subcommittee on strategic forces on the administration's fiscal year 2019 budget request for national security space programs.

President Trump signs an executive order. (Image credit: White House)

Also at the witness table were Gen. John 'Jay' Raymond, commander of Air Force Space Command, and Betty Sapp, director of the National Reconnaissance Office.

Subcommittee Chairman Rep. Mike Rogers (R-Ala.), who has led a congressional push to create a space corps, was visibly giddy. "I am so excited to have the support of President Trump as we work towards this goal and look forward to making it a reality in the near future," he said.

Then Rogers pressed Rapuano to explain how the Pentagon plans to "implement the president's direction."

Rapuano said a reorganization of the military's space component is being studied, as required by legislation passed last year. He said Trump would support any option that provides an adequate solution to the problem. "The president is very focused on outcomes," he said. "He has prioritized space. He recognized the threats that have evolved, and the pace at which they evolve. He's very interested in exploring any options that can provide enhanced capabilities."

A review of how space forces might be organized is being led by Deputy Defense Secretary Patrick Shanahan. "The assessment of the space corps is one of those options that is getting close attention, among others," said Rapuano. Shanahan will submit recommendation to lawmakers in August.

Rogers suggested that Trump's endorsement of a space force essentially validates what his committee has been trying to do. "This hearing could not have come at a better time," he said. "The Air Force has a lot of challenges in dealing with national security space."

The United States faces "strategic competitors" in space, said Rogers. "Like they say in Alabama: If you can't roll with the big dogs you should stay on the front porch."

Rogers approved of the Air Force's actions to increase spending on space systems and to start transitioning legacy satellites to more resilient constellations. "However, I still have concerns about the Air Force's ability to move quickly and get the space segment, ground segment, and terminals all delivered on time and on schedule. I also remain concerned about the prioritization of space programs across the DoD and within the Air Force."

But he complained that the Air Force's wish list of "unfunded priorities" includes more than $350 million in space programs. "That's really my biggest frustration. We've heard Air Force leaders talk about the increasing threats we face in space and declare that space is a priority mission. Yet, when the rubber meets the road, we see space programs given a backseat behind other Air Force programs. I didn't see a lot of air dominance programs on that unfunded list."

Given the president's remarks on Tuesday, he said, "I anticipate that the department will accelerate its plans to embrace the formation of an independent space force."

The subcommittee's ranking Democrat Rep. Jim Cooper, of Tennessee, has been in lockstep with Rogers on this issue. He has made a point in the past that the space corps enjoys bipartisan support. "Note the excellent attendance by our Democratic colleagues," he said at the hearing.

Most of the members, however, decided to save their questions for a classified session after the public hearing.

Raymond defended the Air Force's efforts to put an "increased focus on space superiority." He said the budget funded new capabilities, training and testing. "We still have the best space capabilities in the world," Raymond said. "We have competitors that are moving very quick and we have to pick up the pace to stay ahead of that threat." He noted the Air Force increased space funding by $7 billion over the next five years.

Rogers asked Raymond to submit a report explaining whether he has the resources he needs.

This story was provided by SpaceNews, dedicated to covering all aspects of the space industry.