Why the US Missile Defense System Won't Work

Published Feb 6, 2018

Physicist Dr. Laura Grego explains in lay terms just why the US ground-based midcourse missile defense system—the one that is supposed to intercept a North Korean missile—doesn't work.

In this episode
  • Laura breaks down the different types of missile defense systems in the US and the costs
  • Colleen learns where our missile defense system falls short and asks if there are better alternatives
  • Laura lists the steps the US needs to take to lower the risk of nuclear conflict
  • Laura explains how missile defense systems can actually increase threats around us
  • Laura shares the one thing she wants people to know about missile defense
Related content
Full transcript

Welcome to the Got Science Podcast, I’m your host Colleen MacDonald. Today we’re talking about the importance of things working, whether it’s our missile defense system or database system. A few weekends ago, 1.5 million Hawaiians plus thousands of tourists were sent into a panic when a text alert announced a ballistic missile was headed to the islands. Thankfully it was a false alarm and blamed on human error. This scary incident had many of us reflection on how we would be protected if such a thing were actually real. After all the US has spent hundreds of millions of dollars on missile defense. Shouldn’t it be possible to intercept and shoot down missiles before they reach Hawaii or any other American target? My colleague, Dr. Laura Grego, is a real life rocket scientists and senior scientists with our global security program here at the Union of Concerned Scientists. She’s an expert on outer space security, including missile defense. She spent many years researching and writing about the ground based midcourse defense system; which is supposed to able to shoot down fast moving missiles carrying nuclear weapons. The benefit of having a missile defense expert as a co-worker is that you get the truth about what our systems are capable of. The drawback of having a missile defense expert as a co-worker is that you get the trust about what our systems are capable of. Laura joined the Got Science? team to crush our delusions about our own safety, and also to chat about why having a flawed system is worse than now system at all, why diplomacy is still the only answer to nuclear sabre rattling, and why if you happen to encounter a bear it’s always better not to poke it.

Colleen: So Laura, thanks for joining us today, on the "Got Science?" podcast.

Laura: I'm so glad to be here, Colleen.

Colleen: Excellent. So I wanna start right off the bat with North Korea because that's what's in the news these days. They are ramping up their missile launching capabilities, substantially, and this has put a lot of focus on our Ground-Based Midcourse Defense system. Can you give us just a brief lay of the land to start in terms of the different types of defense systems we have?

Laura: So the United States is in a very fortunate geographical position. We have vast oceans to the east and west and friendly neighbors to the north and south. So we don't spend a lot of time thinking about short-range missile threats because we don't, you know, we have a pretty friendly neighborhood. So when you're thinking about nuclear and ballistic missiles, you know, targeted against the United States itself, we're thinking about intercontinental ballistic missiles, meaning they have to go, 10,000 kilometers at least to get here. So those are the highest, fastest, farthest missiles.

So the Ground-Based Midcourse Missile Defense, the GMD system that you mentioned is the sole system that's meant to defend against threats like that. So that consists of 44 interceptors, all but 4 of those are in Alaska. The rest of them are in California at Vandenberg Air Force Base, near Santa Barbara, and those are meant to knock down a missile that's headed our way. So there are other missile defense systems that you might have heard about and those are meant to defend against shorter-range missile threats. So things that don't go quite that far, and they're used, they call them theater missile defenses or regional. So we have the Aegis ship-based missile defense system, so those are based on Navy ships that move to the area of concern. We've got those in Europe and we have those in East Asia, for example.

And then there is the THAAD missile defense system, which is a shorter range than Aegis mostly and that's an army system that gets airlifted over to wherever you're worried about and they put it down, and they put down radars and interceptors. So that was recently deployed to South Korea, in the south and there's one in Guam, and then there are, you know, even shorter range than that Patriot missile defense systems which people have probably been hearing about for a long time, those were important during the Gulf War. So those are for shorter-range missiles. So there's a range of them but they do different things. So, you know, you could think missiles that don't go as far, also, don't need to go as fast. So that's just easier problem to solve. But by the time you get into intercontinental ballistic missiles, they're going really fast. So it's a super challenging problem.

Colleen: Describe to me what midcourse defense system is.

Laura: Sure, okay. So an ICBM, intercontinental ballistic missile looks like a big space launch vehicle, basically. If you ever watched a launch on TV, you see, something on a launch pad and it's…this big, you know, flames and powerful engines because they need to get this going really fast to get to go as far as it needs to go. So it has this big powerful launch that's called "the boost phase." So that time of active launching lasts, like, at most around five minutes. Okay, so that gets the missile going really fast. And then it's basically...the word ballistic, just basically means it's in freefall.

Once you get it going fast, it's not guided. It's not like an airplane that uses aerodynamics to make changes or to fly, it's simply just going with the speed it got revved up to. So that cruising part, that ballistic flight, that's the midcourse. So most of that travel to go from, for example, North Korea to the United States or somewhere far like that, most of that happens up in the vacuum of space, you know, well above the International Space Station. All right, so up where the satellites are. And so that's the vacuum of space and then it spends a very short time coming back through the atmosphere on the other end, and so more like a minute or two. So most of the time, its traveling is in the midcourse.

Colleen: So that's where our GMD is trying to knock this thing out or explode it?

Laura: Right. So it lasts the longest so that it seems like, that's the first place you start trying to defend. The tricky thing about midcourse and this is, not just tricky, this is a showstopper, is that you're traveling in the vacuum of space and so there's no atmosphere to slow light objects down more than heavy objects. You know, like, if you're standing at the top of the building and you dropped an anvil and a feather, everyone's intuition tells them which one's gonna land first because there's more air resistance per mass, right? So it doesn't work the same way.

And so to distinguish a light balloon that looks a lot like a warhead from the actual warhead, you can't use the atmospheric slowdown to tell you which one is which. You need other clues, you need sensors like radars and infrared sensors to try to gather your clues and figure out which is which, and that's actually a very difficult basic physics problem. And the adversary has lots of tools at his or her disposal to try to trick you, we call those countermeasures. So these decoys that I mentioned like fake warheads, if you can't distinguish between the light fake warhead and the real warhead, you're gonna have to target both of them.

And if your light fake warhead, you know, they don't cost too much to put on top of your rocket because of light, you can put dozens of them and make it really hard for the defense to find out which is the right target. That's an issue that's been well-known for decades and really has not been solved in any substantial way. So the success of a midcourse system really rides on the fact that you just hope that your adversary can't do it. You hope your adversary hasn't figured out how to make these balloons, or good countermeasures, or, you know, little heaters, or coolers or things to change the observed temperature of your objects, you just have to hope that they haven't done a good job with that.

Colleen: So what do you say to the person who says, "Well, just shoot, you know, a dozen...?"

Laura: Interceptors?

Colleen: Interceptors, yes. "So just shoot a dozen interceptors and get all of the decoys and the real one."

Laura: Well, sure. I would say that the GMD interceptors are, like...I think they're, like, $70 million each and you are always gonna be on the wrong side of that cost curve and that is something you hear over and over from the Pentagon, "We are in the wrong side of the cost curve with this system." They acknowledge that that's a problem. It's clearly understood by lots of people in the Pentagon that you're not gonna get out ahead of these decoys by building more interceptors, it's simply too difficult and too expensive. To make a successful system you either gonna have to hope that your adversary is really clumsy and hasn't figured out how to do this or that you have figured out some clever way with your sensors to defeat this countermeasure issue, and it's really difficult to do.

The intelligence community's assessment, you know, almost 20 years ago, was that any country that has the technical capability to build an intercontinental ballistic missile has a technical capability to build these kinds of countermeasures which should fool a missile system. Right, it's unsolved, right?

Colleen: So we keep pouring money into it. We know it doesn't work and it's there, what do we do with it? Stop funding it and...? What are the alternatives?

Laura: That's a great question, right? You know, that was the...I think the George W. Bush administration's made is that if we just get in the ground, it's gonna be hard to rethink it and so people will only want to just go ahead and that was, you know, in the early 2000s. The approach was, "We have no time to do all this engineering and to do more testing research and development, we need to get it in the ground as soon as possible because this threat is happening."

Colleen: Right. And that's at the point in time where the administration decided that they didn't need to go through the rigorous checks and balances of the scientific process.

Laura: Right. So over decades of building military systems, you know, Congress and the Pentagon, they came up with a system of, it sounds so boring, right? Procurement or research and development. But basically, a system colloquially called "Fly Before You Buy" which is basically, how do you build something so that it works like you think it should. It solves the problem you want it to and then it does it in a cost-effective way. So it's just like basics, like, "This is the problem we have. Here's how we're gonna solve it. Here's the research and development. Here's the early stuff."

You get out the kinks, and when you think that you've solved those problems you can build some, try it out in realistic conditions to make sure you didn't miss anything, like, it doesn't work in the rain, or we haven't solved the countermeasures problem, or, you know, it shakes too much and, you know, we can't count on the guidance because it vibrates too much. You work all of those kinks out, and then you buy it, and then you put it into the field. Right? That's the, sort of, the way you would build something that you wanted to work well.

But it was essentially, like, "We can't wait for that process. We're gonna take it out of that system, that basically almost every other thing in the Pentagon has to go through and just build this missile defense system, you know, as fast as possible." So, essentially, it took the technology that existed, stopped the engineering cycles and just built stuff and put it into the ground, it's sort of fast and furious and that's what we have with the GMD, the Ground-Based Midcourse Defense.

So what we ended up having is a bunch of stuff that, as you tested it, it's like, "Whoa, okay. Boy, we missed something here." You know, some of the tests were just basic quality control problems and, you know, a wire had not apparently been attached well enough. But then there are other problems that weren't design problems that they needed to figure out. I understand how you would be confused by the fact that we've built a system, spent tens of billions of dollar, it exists, and yet essentially, it's like a prototype system. It never went through the rigors engineering and that's reflected basically in its test record which is really poor.

Colleen: It's also misleading the public. Because it exists and I would assume that...many, many people would assume that it works or it works well enough and you get conflicting information now from the Trump administration about its success rate.

Laura: Right. So it exists, right? So you think it should work. We spent lots of money and we are continuing to and we're proposing to spend many more billions of dollars on it. So, again, we think it should work, not only the Trump administration but stretching back through the Obama administration and the George W. Bush administration, government military administration officials saying, "This system protects us." Well, right now, really against all evidence, there had been, sort of, no tests that demonstrated that it worked, right? So you're, sort of, taking it on faith.

And maybe, you know, maybe that was satisfying and in some sense to some people, at that point but as the North Korean missile program advanced, I think more people are turning a critical eye and saying, "Okay, so let's see how...can you back that up with real evidence. Does the system really work like that?" And you look at the test program. And one of the beautiful things we have in this country is transparency about a lot, and it's very difficult to hide a missile defense test. They're big, loud, hard to hide type of thing, you know, big rocket launches. So you know when they happen and you know whether they worked or not. So we know a lot about the system and how its performed and, you know, that doesn't square with the claims that it protects American people right now.

[Break: We’ll be back in a minute with the second half of our interview]

Colleen: So let's think about this scenario, you're having dinner with some friends, they're super smart, and you're saying that you don't think spending billions of dollars for a missile defense system that doesn't work is the way to go. And whenever you bring this up, the automatic response is, "Well, if we don't keep working on it or have something like that, you know, we're sitting ducks." So how do you answer that question?

Laura: Yeah. Well, like, I'm pretty sympathetic to that and a lot of what you'll hear, you know, a lot of the automatic reaction is something's better than nothing, even if it's terrible, something is better than nothing. And that sounds, kind of, right, but I don't think it's actually right and here's why. So missile defense isn't like, "It works in a vacuum of space, but it doesn't work in a..." it's not in a strategic or political vacuum. So all your decisions that you make, in general, need to be based on a clear assessment of how it works.

For example, let's say you have a missile defense system that doesn't work very well, like we don't but you think it does. You might be inclined to take more risks in your foreign policy and brinksmanship and, you know, you think you have a shield, you go poke the bear, but your shield actually isn't great, right? So you might not have gone to poke the bear in the first place if you knew your shield didn't work so well. I mean, having a shield is better than not, but best of all is not to go poke a bear, right?

So you don't want a system to distort your decision-making because you think it works better than it does or you might not have as much domestic pressure to find creative diplomatic solutions to a hard problem like the North Korean problem because you, kind of, deflate that pressure because you can say, "Well, we got a missile defense. We're working on this, we don't need to do this hard work of diplomacy because we've got a missile defense."

But if you have things that make you make worse decisions overall and really...like, a missile defense, even if we did a great job on the GMD, even if it worked much better than it does, it still would not ever work 100%. It still would be overwhelmed. It's still in an attack of the way a real adversary would attack. I mean, maybe if North Korea were like, "Yeah we're gonna send one or two bare simple missiles, no countermeasures, really easy, just a couple." You know, maybe the system would have a fair chance of that, but when would North Korea think about doing something like that. I mean North Korea would assuredly no longer exist if it sent any nuclear-armed missiles towards the United States. Whether or not we intercepted them or not, they would have to assume that they would…

Colleen: Perish.

Laura: ...perish. Yes, exactly, right. So maybe it works in this small situation, but that's not the likely situation. If North Korea had decided, I just don't see how it would be likely that North Korea would take the decision to attack the United States. I think it's very unlikely. But if so it would do it, you know, throw everything at us as possible to make it successful. So in that case, you know, the GMD system is not likely to catch everything. So when you're thinking about, "Where do I put my resources? How do I spend my time? How do I spend my political capital? How do I spend my energy?" Really, the problem is, "How do we make sure these missiles are never launched in the first place, right? That has to be your focus. So if missile defense becomes a distraction from that, that's where I see that something may not be better than nothing.

You know, well, I don't think North Korea is gonna have...has an intention to launch intentionally, thoughtfully, nuclear-armed missiles towards the United States, but it's more likely that we'll stumble into a crisis. We'll stumble into because we've got, you know, a fairly impulsive head of state in the United States and we don't have good relationship with North Korea. We don't have good communications that could reliably ratchet crises down or misunderstandings, you say, "Is this what you're intending? This is how we see the problems."

We're not doing that basic to work together that you need to do to make sure you don't accidentally get into a nuclear conflict. So that, and when we're talking about where our energy and our time is and when we're talking about diplomacy engagement, we have to do that part just to make sure that we lower the risk of accidentally doing this.

Colleen: And it's that the turnaround time is so short, you hardly have any time to figure out if...if a real crisis happens, you don't want to have to make that horrible decision in 10 or 20 minutes.

Laura: Well that is the way we’ve set up nuclear weapons and nuclear missiles. Is that they can be used very quickly and on demand, rather than for example taking nuclear weapons off the missiles and only putting them on later after deliberation.

Colleen: Well, it felt just last week with the alert in Hawaii that terrified people. For me, that struck a chord because I remember growing up, I was at the, sort of, the tail end of duck and cover where, you know, a nuclear warhead is coming in and that was a terrifying time. I remember as a kid being very scared about nuclear war and that...I can't imagine how people felt getting that text message. I mean, what do you do? Where do you go? You know, and I don't know on the alert if it said it was a nuclear weapon or...I don't know. Could you tell from the alert if it was or you'd just assume that?

Laura: That's a good question, actually. I don't know the details about that. I think it was, "Take cover." But, you know, it's a different...you know, there are a lot of people who didn't grow up during the Cold War now and who didn't watch wargames and who don't...so it's a different right there. Their life experience has been different. So this may be, sort of, shocking, "Wait, what? I thought we, sort of, sorted with this nuclear weapons stuff out like decades ago." It sounds a little old-fashioned but it's still with us. We still have these. These are still shaping the way we live in this world and in a not positive way. So, I think, people are more aware of it than they have been.

Colleen: Maybe that will be a good thing, maybe it will raise awareness. One other thing that we didn't really touch on but we're talking about, North Korea, and the U.S., and our missile defense system, but this is all in the much larger context of other big countries with nuclear weapons and just how complicated it is. If we make this one move to beef up our security that might look like we're threatening another larger country, maybe we're threatening China now.

Laura: Right. So going back to your friend at the dinner party who is like, "Why wouldn't we wanna have this?" There is yet another piece and you've landed on it which is the potential for missile defense to increase the threats that you see against you. So, you know, sometimes people say, "Oh, it's gonna dissuade countries from building missiles, in the first place, because they're gonna see this impenetrable wall and be like, "I'm not gonna bother." We don't really see any evidence of that, you know, the GMD system has been on an accelerated schedule since 2001 and that coincides with the North Korean. You know, they clearly didn't look at this and say, "We shouldn't bother."

So that's one thing it does, but the other thing is even though it's demonstrated to not work very well in the United States, we're not saying, like, "But here's the horizon. This is when it works like this and it can tackle this threat, that's when we're done." So countries like Russia and China who are thinking about their own nuclear pasture and thinking about, "How do we keep a deterrence balance with the U.S.," they look at the missile defense and say, "How do we incorporate this into our decision-making?"

And we can see that this provides an incentive for them to build more or more sophisticated types of nuclear weapons that overcome missile defenses, maybe not this particular system but where they think the U.S. might be going. So what that does is increase the threats that we see against us rather than trying to find a way to draw down these hugely destructive nuclear weapons as an incentive to increase their sophistication and their numbers. So we'll be paying a price for having a missile defense system.

You will pay that and also in the long-term future where you're hoping that countries reduce the number of nuclear weapons, you know, that will be a factor. So you have to balance what you think you're getting out of it with the price you have to pay in terms of, you know, the fooling yourselves into a more dangerous foreign policy or seeing more nuclear weapons aimed against you and you have to try to overcome your missile defenses, all sorts of things. You have to balance against what you've decided to build.

Colleen: Well, if there was one thing that you could make people understand about weapons and missile defense, if you could just put this thought into the minds of people, what would you want?

Laura: Yeah. I guess what I would say is that the way you should be thinking about missile defense is not that it solves this problem and it doesn't even do a great job of making it less hard to solve. You're still gonna have to do the hard work of diplomacy to find a real solution and real security for all actors. And in fact, if you're not careful, you might fool yourself into thinking it does something more for you than it does, and it might actually be harmful, you know, counter-intuitively. It might end up making your world more dangerous.

My colleague says it this way, "Missile defense often sounds better after 30 seconds than it does after 3 minutes." It's really appealing to think that we could build something technologically to make ourselves invulnerable. I see the appeal of that, but missile defense doesn't do that. It doesn't solve your problem for you. And in fact, it might be a red herring and pull you off the hard task which is dealing with the root of the problem. So it doesn't save your bacon, you need to fix the problems diplomatically.

Colleen: Well, Laura, thanks for joining us today. I hope you have some ways to have fun and not think about this dreary subject that you live every day.

Laura: Yeah. You know, always making yin with a yang.

Colleen: Yes, indeed.

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