Space-based missile defense. Again?

October 1, 2015
Laura Grego
Senior Scientist

UPDATE: In September 2018, UCS released an animated feature and video that explains how space-based missile defense works. Check it out here.

The concept of zombies, coopted and corrupted as it has been over time, seems to follow the cultural moment. Apparently, the idea of a creature that persistently gets up after it’s good and knocked down really resonates with Americans. (I agree with the commentators who suggest we have reached “peak zombie.”) Clearly, however, Congress is not on the cultural vanguard, and seems not to have gotten the message that we are all set with the undead.

For Congress seems ready to reanimate one of its favorite hard-to-kill ideas: space-based missile defense.

(Nodding here to Theresa Hitchens, who suggested Thor’s hammer might do the trick.)

Specifically, this week it will pass an annual defense bill that directs the Missile Defense Agency to

“commence the concept definition of a space-based ballistic missile intercept layer to the ballistic missile defense system that provides— (1) a boost-phase layer for missile defense; or (2) additional defensive options against direct ascent anti-satellite weapons, hypersonic glide vehicles, and maneuvering reentry vehicles.”


A mashup of cultural references hopelessly past their peak. (Source: Mark Baker)

Wash, Rinse, Repeat

It has been more than thirty years since the denouement of Ronald Reagan’s fanciful Star Wars concept and more than twenty since Brilliant Pebbles, its more limited but still space-based descendant, was cancelled. It’s been twelve years since the American Physical Society’s (APS) in-depth analysis concluded that a system of space-based interceptors “would require a fleet of a thousand or more orbiting satellites just to intercept a single missile” and that “deploying such a fleet would require a five- to tenfold increase in the United States’ annual space-launch capabilities.” And six years since the Obama administration set aside the George W. Bush era plan to build a Space-based Test Bed.

And it’s been three years since the National Academy of Sciences (NAS) was asked to weigh in authoritatively on boost-phase missile defense and judged that space-based missile defense would be “10 times as expensive as any other alternatives, at least $300 billion for a limited capability.” Besides the fact that a great many interceptors would be necessary and would be enormously costly, space-based missile defenses are vulnerable to being overwhelmed or defeated. (We prepared a fact sheet that details these shortcomings.)

What might have changed in the interim to make space-based missile defense a concept worth revisiting? I can’t think of anything. And the Pentagon seems to have concluded that the idea is not worth pursuing either, as the idea is not even mentioned in the Pentagon-led 2010 Ballistic Missile Defense Review Report.

Unfortunately, members of Congress haven’t seemed to have learned the lesson, and in this new study they will force the Pentagon to go back again to get the same answers that we already know.

The only bright side is that included in the study is the requirement that the Director of the MDA submit:

(2) a plan for developing one or more programs of record for a space-based ballistic missile intercept layer, including estimates of the appropriate identifiable costs of each such potential program of record; and (3) the views of the Director regarding such findings and plan.

The costs are sure to be enormous and to put the potential capabilities of space-based missile defense into perspective. There’s no mystery there, except maybe the mystery of why Congress cannot seem to resist returning again to unfertile ground.