WASHINGTON: The head of Air Force Space Command worries that tightening defense budgets and looming force structure cuts could reduce his critical space and cyber capabilities.

“Because these capabilities are so vital, and the need to maintain local and global capabilities, space and cyber capability doesn’t really scale well with force structure reductions,” Air Force Gen. William Shelton said Wednesday. “You either maintain global coverage or you don’t.”

Space Command must maintain force structure “in this fiscally constrained environment,” he said. The budget “is always at risk,” he said, particularly “at times like this, when there are a lot of people out there with their budget knives out.” But, he added, “this is kind of a one or zero game. You either provide the kind of coverage needed to have full capability, or you don’t.”

At the same time, Shelton warned that producing national security satellites and the costs of launching them are “unsustainable.” That limits America’s abilities to replace them and increases our vulnerability should any be lost to either hostile acts or to accidents.

Shelton focused heavily on programs or proposals to reduce the cost of space assets, noting that “the satellites we currently employ are clearly technological marvels. They take years to hand build and deploy” and are “very expensive. Consequently, we build the absolute minimum number of satellites, just in time and we don’t build spares.”

That minimal infrastructure increases the risk of lost capabilities, he warned. Smaller satellites also would be cheaper to launch, and could enable putting multiple payloads on a single launch vehicle.

While praising the string of 80 successful launches of national security satellites since 1999 and the “wonderful relationship” the Air Force has with the United Launch Alliance, Shelton said the cost of space launch “is just not sustainable for us.”

They are working to reduce launch cost by a block buy program and by trying to encourage other firms — like the recently successful SpaceX — to get into the space launch business, he said.

To reduce U.S. vulnerability, Shelton suggested building smaller, less complex satellites, which would be less expensive. That could allow his command to put more in orbit. (This sounds a great deal like Operationally Responsive Space, once-spurned by many at Space Command.)

“At a minimum, this certainly would complicate an adversary’s targeting problems” and would provide more protection from “a catastrophic cheap shot or an unfortunate collision.”

Shelton also added his voice to the growing chorus of officials warning about the increased risk in the cyber domain, “where the price of admission is low, the attribution of nefarious acts often very difficult” and the legal and policy aspects are uncertain.”

“Millions of probes are launched every day” against government and private computer networks, he said. “Critical infrastructure is at risk.”

Shelton appeared to be anticipating the battles over defense budgets that are expected in the next session of Congress. President Barack Obama, who won reelection Tuesday, has proposed $487 billion in cuts to future years defense budgets and reductions in forces, primarily affecting the Army and Marine Corps.