Assuming it can be done, why would using an orbital laser constellation be an attractive approach for doing ballistic missile defense (BMD)?

• A. It would be so intimidating to potential adversaries that they would not dare trying to launch a ballistic missile.
• B. It would be able to shoot ballistic missiles in boost phase, whereas terrestrial-based weapons cannot when the targets are over the horizon.
• C. It would be a system with limitless shots.
• D. An orbital laser constellation is less expensive than terrestrial-based BMD weapons.

Answer: (B)

The main idea is that a laser in orbit can directly engage a missile during its boost phase even when the missile is over the horizon from any ground-based defense. From space, a laser constellation has a clear line of sight to launches anywhere on the globe, so it can target the booster while it’s still burning and the missile is relatively large and detectable. Intercepting in boost phase is appealing because you hit the missile early in its flight, before it releases decoys or debris changes its profile, and you take advantage of the high-energy window when destruction is more achievable. Ground-based weapons, constrained by the curvature of the Earth and limited radar visibility, can lose sight of a launch over the horizon, making boost-phase interception difficult or impossible from a single terrestrial site.

Other options miss this core advantage. Using intimidation as a tactic doesn’t address the engineering hurdle or the interception capability; imagining limitless shots ignores real limits on laser power, energy, and platform readiness; and assuming lower cost ignores the substantial expenses and complexities of deploying and maintaining a space-based laser system. The key, then, is the uninterrupted, global line of sight from space that enables boost-phase engagement.