No, Space-Based Missile Defense Will Not Cost Only $20 Billion. (Spoiler: That’s only the launch costs.)

September 24, 2018 | 11:17 am
Laura Grego
Research Director, Senior Scientist

Space-based missile defense is a terrible idea. It is expensive and straightforwardly defeated, and it is dangerous and destabilizing. (If you haven’t watched it, please do take a look at this video and web feature UCS just produced. It helps to see these arguments visually.)

But knowledgeable people say it’s not so expensive!

At a recent event hosted by the Missile Defense Advocacy, Under Secretary of Defense for Research and Engineering Mike Griffin calculated the cost to “put up” an interceptor layer. Given how Griffin talked about it, you may be forgiven for thinking he means this is the full cost of a space-based missile defense system—rather than just the cost of launching the interceptors into space. Here’s what Griffin said:

I’ll close by noting that I am very, very, very, very tired of people who say that we cannot afford it. Let me offer just a trial balloon kind of a number. I get tired of hearing how it would cost, you know, 100 or more billion dollars to put up a space-based interceptor layer. If I use as a reasonable, an entirely reasonable number based on experience of $20,000 per kilogram delivered FOB low orbit, and if I were to say that I would be content with a layer of 1,000 interceptors, which seems to me like a lot, and each of them weighs a metric ton—1,000 kilograms—which would seem to me like a lot, then the entire cost of that would be $20 billion.

Read the fine print

You will notice that what Griffin is estimating is only the launch costs for a set of 1,000 interceptors weighing a ton each. I don’t disagree with his arithmetic. But he is not estimating the full cost of developing and building a space-based missile defense system—he is in fact leaving out the majority of the costs of the system.

Griffin does not include in his estimate:

  • the cost of building the interceptors themselves
  • the cost of research and development for the interceptors
  • the cost of building supporting sensors and ground stations for operating 1,000 satellites
  • the operating costs for the system
  • sustainment costs: expected lifetimes for interceptors are 5 to 8 years, so you’d need to send up 125-200 new interceptors per year, on average, to keep a 1,000 satellite constellation healthy.

This also sets aside the fact that the total mass of interceptors needed on orbit is quite sensitive to assumptions such as how many missiles the system is expected to counter, whether those missiles are solid- or liquid-fueled, and the amount of decision time required—conditions that are explored in studies such as those coordinated by the American Physical Society in 2003 and the National Academies of Sciences, Engineering & Medicine in 2012.

The National Academies study concluded that the life cycle costs for even an “austere and limited-capability” set of 650 satellites would be at least $300 billion in 2010 dollars, or 10 times more expensive than other missile defense options they examined. This estimate included the costs that Griffin did not, which are clearly substantial.

(NB: We recently wrote about why a different misunderstanding in circulation is wrong: the suggestion that a small constellation would protect against long-range missiles.)

Ok, so it probably is expensive. Are we worried about destabilizing and dangerous?

Putting interceptors in space will almost certainly provoke a reaction from potential adversaries, be it development of similar weapons, attacks on these interceptors, or an adjustment in their nuclear posture to compensate. None of these actions would improve US or global security.

At the MDAA event Griffin was asked “what do we say to China and Russia?” to allay concerns and avoid conflicts over such a system. Dr. Griffin is not particularly worried about it. He responded:

…somewhere well down on my priority list is caring about what other people think. And we just cannot afford to do that, and by creating a world—by creating a geopolitical policy environment where those kinds of considerations are surfaced, by even allowing ourselves to be drawn into that discussion we do ourselves and our allies and partners a disfavor.

However, also on the panel was Undersecretary for Policy John Rood. Rood noted that Griffin’s job is developing technology and quickly indicated that his own job was looking at just such policy issues, saying:

We do spend a lot of time concerning ourselves with those questions.

And when pressed on the issue that space-based interceptors would present an offensive capability, Undersecretary Rood said that:

…those are bridges yet to be crossed some time away given the level of sort of examination we’ve given the question thus far.

What is the key argument?

Our skepticism about space-based boost-phase missile defense gets mischaracterized, so to be clear: The problem is not that a showstopper technical issue makes hit-to-kill from space unachievable.

But even if the hit-to-kill interceptors worked perfectly, the system would not provide reliable defense since it could be straightforwardly defeated or overwhelmed. At the same time, the system would be very expensive, and a waste of resources that could be much better used elsewhere. And it would be destabilizing and dangerous. (Click here for more details.)