The United States should counter the rising anti-satellite (ASAT) warfare capabilities of nations such as China with a mix of solutions, including readiness of smaller and easily launched replacement satellites along with protective systems to knock down enemy anti-satellite weapons approaching U.S. space-based assets such as satellites.

Merely developing these capabilities could deter enemies from attacking U.S. space-based assets in the first place.

So says Robert Butterworth, president of Aries Analytics, Inc., and a fellow with the George C. Marshall Institute think tank in Washington, writing in a policy outlook paper of the institute.

Replacement satellites lying in readiness for quick launch (48 hours or so) to take the place of satellites destroyed by enemy ASAT attacks could be helpful to U.S. forces, according to the Butterworth paper.

"If launched as replacements for satellites initially lost to enemy action, the supplements would shrink the [enemy] advantage that was sought in attacking the original satellites," the paper states.

To further offset any enemy advantage, the United States could mount a counter-space action to wipe out enemy assets.

"If the U.S. coupled its supplemental replacements with vigorous offensive counterspace actions of its own, an enemy’s initial attacks would leave the U.S. with a diminished yet effective set of space assets, and the enemy with none," the paper reasoned.

"All in all, being able to supplement or restore needed capability in orbit would likely prove a stabilizing and deterring influence," the paper predicted.

Further, the United States could build in defensive systems to its space assets, perhaps using laser gear. "The [U.S. military-owned] target might also be protected by active defenses, although with intercept occurring only about ten minutes after launch, the defenses will probably need to be directed energy rather than kinetic weapons," the paper stated. "Either case would require precise situational awareness — exact information about the technology and operation of the attack — together with major advances in command and control for the defenses."

Currently, the U.S. Missile Defense Agency (MDA) is developing a directed energy system, the Airborne Laser, to knock down enemy ballistic missiles in their early, or boost, phase just after the enemy weapon rises from a launch pad or silo. MDA also has several kinetic energy ballistic missile defense systems, in which a solid missile interceptor slams into an incoming enemy missile to destroy it.

However, MDA hasn’t been charged with developing systems to defend against enemy ASAT threats.

But clearly, developing means of countering enemy ASAT systems would have value, the report argued.

Further, critics and protesters might have difficulty attempting to block such U.S. systems from being developed and brought on line.

That is because, "not being destructive weapons themselves, the supplements could scarcely be considered escalatory," according to the paper.

However, in developing these systems to counter enemy ASAT systems, less is more, according to Butterworth, rather than aiming for big and heavy.

"Timeliness is the key to the projected deterrent effect of supplemental [replacement] satellite systems, and for the next few years, at least, its possibilities are governed by a version of Einstein’s physics. Timeliness is a function of mass: The bigger the satellite, the larger the launcher, the fewer the launch site options, and the longer the time from call-up to orbit."

Another element here is cost.

"Larger satellites are also more expensive, as are larger boosters and longer flight preparations; one can generally expect that the same budget will buy fewer large supplementals than smaller, cheaper ones," Butterworth cautioned.

"Fewer and larger, more and smaller — which package would better suit the needs of joint force commanders? A larger satellite would probably better approximate the capability of the legacy constellation of intelligence/surveillance/reconnaissance (ISR, or "spy") satellites. But with larger numbers come greater capacity, more frequent revisits, a diversity of collection geometries, and more targets to confound enemy planning."

Adding it up, the United States should move toward smaller and cheaper replacement satellites.

"On balance, more and smaller seems the preferred approach, if they can be launched quickly and if they can perform militarily useful functions," the paper concluded.

And it isn’t necessary to reinvent the wheel here.

"The first requirement, quickly responsive launch, can be met right away, using boosters from the Air Force’s longstanding Rocket System Launch Program (RSLP) and mobile range equipment developed by the Air Force Research Laboratory over the last few years," the report observes.

However, this might involve an elaborate system of replacements, needing perhaps 10 satellites in low Earth orbit to replace a downed satellite system.

Clearly, Butterworth says, the United States must face the fact that space as a peaceful domain with a right of free passage for spacecraft may be a relic of a longed-for past.

The fact is, "U.S. space systems are now targets, the inevitable consequence of their integration into U.S. military operations, and some of them can now actually be engaged by some potential adversaries," the report asserts. "Many options are being urged in response, including active defenses, preemptive strikes, retaliation, sharing arrangements with companies and allies, arms control negotiations, and rapid augmentation," the report notes.

And that is all well, as far as it goes.

"Within each option there are competing priorities; in pursuit of rapid augmentation, for example, one can find demands for new industrial practices, common aero vehicles, reusable upper stages, and new launch site developments," the report observed.

Yet before giving any precedence to those concerns, a primal requirement is that, "if priorities are set by military needs, surely an initial operational capability takes precedence."

The full study titled "Assuring Space Support Despite ASATs" can be read at on the Web.