“For half a century, ACA has been providing the world … with advocacy, analysis, and awareness on some of the most critical topics of international peace and security, including on how to achieve our common, shared goal of a world free of nuclear weapons.”

– Izumi Nakamitsu
UN High Representative for Disarmament Affairs
June 2, 2022
Interview With Missile Defense Agency Director Lt. Gen. Henry Obering
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Wade Boese and Miles A. Pomper

President George W. Bush has made fielding missile defenses a priority for his administration. In pursuit of this objective, he withdrew the United States from the 1972 Anti-Ballistic Missile (ABM) Treaty in June 2002. During his administration, he has requested nearly $40 billion in funding for the Pentagon agency charged with developing ballistic missile defenses, and ordered the 2004 deployment of the initial elements of a defense against long-range ballistic missiles. On Sept. 29, Arms Control Today interviewed Air Force Lt. Gen. Henry Obering, who oversees the Pentagon’s Missile Defense Agency (MDA), on the current status of and future plans for U.S. anti-missile systems.

ACT:We appreciate you taking the time to talk to us. Could you provide our readers with a snapshot of the current status of ballistic missile defense efforts, particularly the ground-based midcourse (GMD) system?

Obering: First of all, I want to make a couple of points. The ground-based system is of course the most visible and one of the more complex components of our missile defense system. But it is part of a larger capability that we are building, and that is an integrated ballistic missile defense system. It will consist of space-based sensors, sea-based defenses, land-based defenses—along with sea- and land-based sensors—tied to command and control centers. So, we are building an integrated and layered system.

Now, specifically to the ground-based midcourse system, it is the part of the system that is capable at this point of protecting against long-range missile threats. We attack them in the midcourse phase.[1] Since the summer of 2004, we have been emplacing interceptors at Fort Greely, Alaska, and at Vandenberg, California. We currently have seven interceptors placed at Fort Greely and two in California. They are supported by the Defense Support Program satellites, which we have had for years for early warning purposes, and the Cobra Dane radar in the Aleutian Islands, which we just had a very successful test of. In that test on [Sept. 26], we launched an actual long-range target out of the back of a C-17. It comes down in parachutes and then ignites and comes on a threat trajectory into the defended area across the radar. We proved in that test that we were able to detect, track, classify, and generate a fire-control solution against that missile with the interceptors and the actual hardware and software that we have in an operational configuration today.

ACT:Let me ask you a question on the interceptors placed at Fort Greely. Last October, the appropriate military commands began putting the system through a “shakedown.” Initially, this was described as a process that would last several weeks but it has now been underway for nearly a year and the system is yet to be declared operational. Why is that?

Obering: Well, I do not know who classified that as only being for several weeks.[2] I am unaware of that. What we decided to do was what you would do with any system of this complexity—much like taking a ship on a shakedown cruise. That is what we have been doing since last October.

Let me get to a broader point here for just a second and then come back. We live in a different world then when we signed the ABM Treaty during the Cold War with the Soviet Union. The way that we acquired, produced, developed, and tested [weapon] systems grew up in that Cold War environment. And, to be very frank, there was not a sense of urgency then that we have developed in this day and age. So, we felt we were totally defenseless against a country that would develop a long-range or, even for that matter, a medium-range threat against the United States. We had no defense against that. In [missile defense] testing we did from 2000 to 2002,[3] we successfully intercepted targets. We did that with a prototype of the [exoatmospheric] kill vehicle (EKV)[4] that we have in the ground today. That gave us enough confidence that we had a capability that we ought to start getting out the door; again, because we had no defense at all. Had we been attacked, I would have been hard-pressed to say why I did not try to start getting that capability into the field. So that was the rationale behind starting to put out a defensive line of capabilities. Is it perfect? No. Is it what we are going to have for the future in terms of this idea? No. We are going to continue to improve this.

In fact, we have already had at least two major configuration changes to the system with respect to updated software in the fire control system of the command-and-control and battle management system. We continue to develop and wring those out. We have demonstrated that we can take the system from what we would call a developmental state, where we are upgrading this software or upgrading a configuration, into an operational alert state, and then back. We will continue to do this as we improve and upgrade the system. But the point is that when we are in this development mode we can come out of that into an operational mode should we have to for real-world purposes. That is something that is important. You can continue to build a system and improve it while having that inherent capability.

ACT:Is there going to be a point when you are going to declare the system operational?

Obering: Well, first of all, I do not make that call. I am responsible for developing the system and getting it out there. There are a lot of factors that go into what you declare in terms of the capability, not the least of which, obviously, is the technical readiness or the maturity of the system. From a technical and performance perspective, we have a capability that we can use. Had we followed that classic [development] model that I talked about in the Cold War era, we would just now begin to probably start some of our testing to support a fielding decision, meaning that we would be three or four years away from having any operational defensive capability. We would be launching targets and interceptors in our test bed in the South Pacific, but in terms of a real live operational capability against a real-world threat, we would not have anything.

This idea of concurrent development and test, development and test, development and test, with inherent capability, is a model that we need to pursue for today’s environment. We have used it on other programs. We used it on Global Hawk and on Predator.[5] In this particular instant where you do not have anything, I think it is very appropriate.

ACT:Two years ago, then-Undersecretary of Defense Edward Aldridge predicted the [ground-based] system would have a 90 percent chance of successfully taking out a North Korean ballistic missile. A few months ago you noted that the system has a “better-than-zero” chance of hitting an incoming missile. What accounts for this seemingly large discrepancy and how do you rate the current system’s ability to intercept a ballistic missile warhead?

Obering: What I meant by “better-than-zero” is that if you do not have anything in the field, you have zero. The specific percentage of the system’s effectiveness is classified. That is why I do not articulate what that is. Now, Undersecretary Aldridge made a comment in testimony and I do not know the context of that in terms of how he made or why he made that remark. But I can tell you that not only is it better than zero, which is what we had a year ago, it is much, much better than zero. I just cannot get into what those details are. Nor, I think, would the American public expect that because we do not typically go into those kinds of details for our systems.

ACT:What is that assessment of much, much better than zero based on?

Obering: The testing that we have done to date. It is based on the confidence that we have continued to build in the system. I want to go back and iterate a little bit about that. A lot of times, critics say, “it is untested, it is unproven, etc.” The fact of the matter is the basic functionality of the system—the ability to intercept a target traveling at the speeds that we are talking about,[6] the ability to engage in a terminal engagement and destroy the target—we have seen that in intercepts that we have done in the 2000-2002 timeframe. We took the kill vehicle that accomplished those intercepts and we improved it by making it more producible and making it a more robust design. The booster that we have in the ground today, we have actually flown successfully in the current configuration twice before and in a similar configuration another time. Is the system designed for a very, very complex threat suite? The answer is no. But what it can handle is what we anticipate the threat to be in the near term. We will evolve and improve the system over time to handle what we think the threat is going to evolve to.

ACT:You mentioned testing; there has not been a successful intercept test since October 2002. The interceptors that are deployed now in Alaska and California are comprised of boosters and kill vehicles that have never been flight-tested together. What gives you confidence that these interceptors will work?

Obering: Good question. I want to be a little specific about why we have not had a successful test since 2002. A large measure of that time was to stand down because we thought we had learned as much as we could learn from those tests. We had basically wrung out those configurations as much as we could. A large measure of that stand down was to take the money that we would have had in further testing of that design and put it into the development of the [interceptor] configuration that we have in the holes today.

When we came back up on line last year to begin our flight testing again, we ran into a problem in December and a problem in February.[7] Those problems had nothing to do with the basic functionality of the system. They were basically technical glitches.

In December, we had a software timing issue in the booster; we actually flew with that twice before. It was easily fixed. It was one parameter in one software line of code.

In terms of the February test, we had a ground support arm in a silo that did not clear out of the way. That turned out to be workmanship and a quality control issue. Let me explain. We have two silos down in the South Pacific that we test out of. The particular configuration of the silo that we were testing out of in February happened to be for a booster configuration that is no longer in the program and there had to be some modifications done to that silo to accommodate the booster that we now have in Alaska and California. It was the workmanship surrounding the modifications to that test silo that led to this failure. This was not the rocket science part. We determined that based on workmanship there was some salt air fog that got into the silo. It corroded a hinge and that is what [led to the failure]. We do not have that problem in Alaska or in California with respect to the silos.

Since we had the failures in December and in February, I wanted to make sure that we had wrung everything out. Because when you have two failures in a row like that, even when they are peripheral to the basic functionality of the system, you want to make sure that you do not have any other problems lurking, especially when you talk about quality-control, workmanship, and that type of thing. I established the Independent Review Team to take a look at the program and review every aspect of it, basically soup-to-nuts, and to tell me where we needed to pay attention. They made some great recommendations. Since May, we have been going through the items that they have recommended and we have laid out a systematic test program that we plan to get back into here in a couple of months. In the meantime, we have been taking components of the booster and the kill vehicle and putting them through qualification testing. We have been doing full qualification testing on the booster’s software. So those have been the pacing items to get us back into flight testing.

ACT: You mentioned the Independent Review Team; their conclusion was that there was not enough flight data to validate [testing] models and simulations. Once again, how do you have confidence that the interceptors will work?

Obering: Well, the major conclusion that they had is that there were no design flaws that they could tell in the system. That was one of the primary [findings] they made. You almost never have enough flight test data to validate all the simulations and models that you need. However, I can tell you on the booster flights that we have accomplished for the booster configuration that is sitting in the silos in Alaska and California, we have flown that and those models for the flight test have very accurately predicted the performance of those boosters, including the launch environments and everything else. We have to have more flight test data. There is no doubt about that. But we can now get that data as part of our flight test program and, at the same time, have at least some type of capability, should we need it, to counter an operational real world threat. This is not a game. It tends to be a game sometimes, I think, inside the beltway.

ACT: If I may, what’s the reasoning behind conducting the next two flight tests without a target and then waiting to go back to intercept testing next year?

Obering: First of all, any time that you go through that type of systematic exhaustive review of your program, you want to go back and make sure that you minimize the variability when you resume testing. We want to take this a step at a time now. We are being very conservative to make sure that we have thought through everything.

The rationale for not flying against a target in the next flight test is we want to make sure we can take the kill vehicle through its paces. We are going to be able to do some things with that kill vehicle now that we would not be able to do if we were flying against a target. For example, if there is no target when the kill vehicle opens its eyes, it is going to do some maneuvers that we have not had to do in the recent test program.

The reason we are going to fly the second flight test without a target is because we are going to start launching the interceptor out of an operational site, which is Vandenberg. You do not do that overnight. You have got to make sure that you have tested the crews; that they are ready. Moving to a new site means you have new aspects of range safety and everything else. Therefore, you want to make sure that you have got that right before you go against a target.

Then we introduce targets for the third test and the fourth test.

ACT: Will those be fired from Kodiak [ Island, Alaska]?[8]

Obering: From Kodiak, exactly.

ACT:Our readers, as I am sure you are not surprised, have closely followed the debate over missile defenses and the ABM Treaty. As you know, in December 2001, the president announced that the United States would withdraw from the treaty. How has that withdrawal benefited U.S. missile defense programs?

Obering: Tremendously. Absolutely tremendously. It also benefited arms control. Because, let’s face it, we are the ultimate in arms control. When all else fails, we have to have something between us and a weapon. When attempts to diplomatically disarm other countries fail, we have to perform.

At the time the ABM Treaty was signed in 1972, it was appropriate for the environment that we were in. It was a very good thing because our primary threat at that time was the Soviet Union, which had missiles capable of reaching the United States. The concept of mutually assured destruction was evident; it was stabilizing between the two countries. The lessoned learned from the ABM Treaty is make sure that you have the right treaty with the right nation. In 1972, there were about eight nations around the world that had ballistic missiles or ballistic missile technologies and most of those were friendly to the United States. Today, there are more than 20 countries around the world that have ballistic missiles and ballistic missile technologies and many of those countries are not friendly to the United States or, at least, could be considered hostile to some of our intents and interests. For us to have abided by the ABM Treaty with a country that no longer existed, while the rest of the world were arming themselves with these weapons, flies in the face of responsible defense for the American people. I could not honestly look an American in the face and say that we are providing for the common defense if we are not addressing a threat that was growing around the world.

ACT: Were there specific actions that you would not have been permitted to do under the treaty that you have done since the withdrawal?

Obering: You bet. We could not have built an integrated capability, which you are going to have to do against these types of threats. The ability for us right now to take an Aegis radar[9] and tie information [that it gathers] into a fire control system for a ground-based weapon located in Alaska or California would have been a violation of the treaty. We could not mix strategic and tactical or theater weapons systems together to achieve the capability that we now have and that we will continue to improve.[10] This idea of mixing and matching sensors and interceptors and command-and-control elements to expand your detection and engagement capability over a single, autonomous system would have been prohibited by that treaty. So the ability to even develop and field a capability, other than the one site that was allowed in the treaty, would have been prohibited.

Again, the treaty was a recognition of the environment in which it was written. It is not the environment that we have today. We had to take very realistic steps to address today’s environment and today’s threats. I do not view this as a zero-sum game like some people do. We have to continue diplomatic efforts to try to encourage countries not to invest in weapons of mass destruction. One of the ways you can do that—and I think historically speaking it has always been the case—is through strength. You show them that it is not worth the investment. The ultimate missile defense is if we can dissuade a country from ever investing in ballistic missiles to start with. That is one of the primary objectives. If we cannot do that, we have to find ways to deter them from ever using them, and if they do use them, to destroy them before they harm the American people, our interests, or allies.

ACT: Recently you have endorsed exploring the possibility of space-based interceptors. MDA has plans to possibly begin testing and exploring these systems as early as 2012. When will the United States start having to deploy hardware to create this space-based test bed and why do you think this is necessary?

Obering: That is a great question. Let me preface it this way. Twelve years ago, if you had asked me if we were going to be fighting in Afghanistan, I would not have predicted that. If you can tell me where we are going to be fighting 12 years from now or what threat countries we have to deal with or what those threats will look like and where they are coming from, then I could lay out very precisely a terrestrial-based system that could handle that. But we do not know. We know what we know today and we will continue to evolve that.

There are a lot of things about a space-based interceptor that we do not know that we need to explore from a technical perspective. I think it is also a proper debate to have with the American public and in Congress as to whether we want to do this. But speaking from a military perspective and from somebody who is charged with protecting the American people, deployed U.S. forces, allies, and friends against all ranges of missiles in all phases of their flights, it makes sense to explore a space-based interceptor layer. And, it would be nothing more than that. It would be a layer to the system that we have evolved and will continue to evolve terrestrially. There is a lot that needs to be answered and there needs to be an active debate about whether we want to do this. One of the things that I want to make sure is that it is an informed debate and that is why we think it is prudent to do some experimentation with respect to whether you can even achieve [a space-based layer]? Can you build the responsiveness to command-and-control? Is it affordable? If you have interceptors that are unaffordable in terms of their mass, size, weight, or whatever, there is no use in starting down the path. So what we have proposed is not that we are going to actively build a space-based layer. What we have proposed is a very modest and moderate test bed approach to launch some experiments. We have a very modest amount of money beginning in the 2008 timeframe to begin to do this experimentation. The debate can take place in parallel to that and hopefully it will be a much more informed debate than we have today.

ACT:What about those who would point out that initially the Fort Greely site started out as a test bed site and then it was turned into an operational site so why couldn’t a space-based test bed become a deployment site just by changing its name?

Obering: Well, when we took the Fort Greely site as a test bed and it became basically a site with an operational capability, it was done for a good reason. There was a recognition that we had an emerging threat. We had a threat from North Korea and we had to do something about that.[11] I would anticipate that we would not have an operational space-based interceptor layer unless we needed it. But these defenses take time so being able to go from a test bed into an operational status in a very short amount of time is something that is an advantage, not a disadvantage.

ACT:What about the concerns of Russia, China, and others that this could set off an arms race in space?

Obering: The Russians and the Chinese understand, or at least should understand, that the scale of what we are doing nowhere near matches what they can amass in terms of attack profiles and quantities. We are not talking about a massive Brilliant Pebbles[12] or a massive space-based interceptor constellation that would come anywhere near close to countering a Russian or Chinese threat. We are not talking about that. We are talking about a modest layer to help us engage emerging threats that could occur around the world over the next decade. Now, some people also describe this as the weaponization of space. That is a term that we do not do enough examination of. What we are talking about doing—if this pans out—is putting very small-scale interceptors into space that would be defensive weapons. They would have no offensive capability. They would have no ability to attack anything on the ground. They would not have the survivability to come back through the atmosphere.

ACT:They could attack satellites in space.

Obering: It depends on how we design them. It depends on what their intent and their use are. A warhead traveling through space and a satellite traveling through space are very different. These have to be considered defensive weapons because, again, just by design and by the nature of what we are talking about. But I am not the one to decide that. All I am charged to do is to try to make sure that we have thought through the technical aspects and that we have got an informed debate. This is a decision that needs to be made by the American people and, obviously, debated in Congress.

ACT: How many interceptors, in general, are we talking about for a test bed in space?

Obering: Not even a handful to start with. We are talking about onesies, twosies in terms of experimentation. That is all we are talking about.

ACT: There are also concerns about the creation of space debris. What is your perspective on that issue?

 Obering: I think there is a lot of misunderstanding about that. I think there is a lot we still need to work out and think through about debris. By the way, we intercept in space today. Our intercepts for the GMD system and for Aegis occur in space today. So we understand and know how to handle debris issues associated with a test bed. Debris is somewhat of a side issue. I know we have folks that are actively looking and exploring it. But you can get different opinions of that depending on which side you engage.

ACT: Back on Earth, could you update us on U.S. plans to deploy long-range interceptors in Europe?

Obering: We have money that has been budgeted beginning in the 2006 timeframe for this, and we think it is important for a variety of reasons. Part of our strategy is not only to protect the U.S. homeland, but also to protect our deployed forces, our allies, and friends. We are concerned about threats that may emerge from the Middle East. Having another interceptor site in Europe would greatly [complicate] not only an attacker’s problem with respect to the United States in terms of how many interceptor sites they have to deal with, but it also primarily provides coverage to our allies and friends. There are several nations in Europe that are very interested in hosting a third interceptor site and we will continue to pursue that over the next year.[13]

ACT: Has there been any determination made whether these would be the ground-based midcourse interceptors or Kinetic Energy Interceptors?[14]

Obering: Like anything else we do, we try to crawl, walk, and then run. The only interceptors that would be available in the near term would be the ground-based midcourse interceptors that we have today in Alaska and California. If we can evolve this Kinetic Energy Interceptor, which I think would be a tremendous addition to our capability, then that is another option we could offer for the future.

ACT:Has there been any determination on which European country will host interceptors?

Obering: No, not yet.

ACT: Is there a general timeframe? You said the money begins in 2006, but when might interceptors be deployed to Europe?

Obering: Well, we are going to have to have a fairly sound, solid foundation of agreement in the next several months so that we can begin to move out with the program.

 ACT: Spending on all missile defense-related activities over the past several years has been approximately $9 billion annually. Do you foresee future spending remaining about the same and approximately how much do you think bringing a layered missile defense system on line will cost?

Obering: I think this year we have asked for $7.8 billion in the president’s budget.

ACT: Is that MDA or all missile defense-related funding?

Obering: That’s the MDA budget, $7.8 billion.[15] It is about $6.4 billion in development and about $1.4 billion in fielding or deployment capabilities. And that stays pretty constant across the [Future Years Defense Plan] in terms of that investment. We will manage within that. Do I think that that is going to stay that way? I think that we are facing tremendous budget pressures and that [MDA] is part of that mix. We have to be involved and we have to be part of that discussion in terms of what that budget authority would be.

But in terms of affordability, let me put it to you this way. If you look at every penny that we have spent on missile defense since 1983 when President Ronald Reagan started the effort, it is about $92 billion. That is every penny that has been appropriated to missile defense. If you look at the Sept. 11 attack on New York City, the direct damage cost alone, as reported by the [Government Accountability Office] in 2002, is about $83 billion. That does not have anything to do with economic opportunity cost or anything like that. So in one attack that did not include a weapon of mass destruction, you have almost reached the total investment line of what we have done over 22 years in missile defense. It is not just how much does the system cost. It is what is that return on investment and are we getting that return on investment for the American people? [Missile defense] is a small fraction of the overall defense budget. I believe that the return on that is very well worth it because had we had an attack of a weapon of mass destruction on an American city like New York or Los Angeles or even Washington, you would not believe the damage cost. If we can prevent or interdict that, it is well worth the investment.

Another thing people ask me is “Well, what about weapons of mass destruction in suitcases or in ships off the coast or smuggled in?” It is not an either/or. We have to be prepared for all of those, unfortunately, in this day and age, I wish it was not like that but wishing is not a strategy. We have to be prepared for all eventualities.

ACT: Going back to testing, there are some people that have read the Independent Review Team report as suggesting that MDA should cut back on its flight testing to avoid failures that might undercut the system’s deterrent value in a potential adversary’s eyes. Is this an accurate reading of the report or the strategy behind MDA’s delay in resuming intercept testing [of the ground-based midcourse system]?

Obering: Absolutely not. When we get back into the air in our test program—and we believe that that will be in the next couple of months here—then we plan to fly four times in 12 months. That is a much increased pace over what we have done in the past.

And, by the way, that is just one part of [missile defense testing]. We also have the Aegis program, which we flight-tested last February. That was very successful. We are going to flight-test that again in November. Next year in the [Terminal High Altitude Air Defense][16] program, the Aegis program, and the GMD program, we will have approximately 10 flight tests if you add all those up. That is a very aggressive test program. We are not sitting on our hands and trying to effect any type of delay because of that consideration.

ACT: One program you did not mention was the Airborne Laser.[17] Where does that program stand? We know there has been some difficulty in bringing that on line.

Obering: Actually, we have had tremendous success since last November. It was a program when I came to the agency that was what I would consider to be unstable. They were losing schedule. They were not making sufficient progress. There was a concerted effort made over the past year and a half to restructure and refocus on the major milestones. And, by the way, this is a good example of making sure that you have focused on the proper things. Two years ago or more, we were worrying about maintainability and spending resources on that when we had not even fired the laser yet.

Last November, we achieved first light in the laser and we achieved first flight of the heavily modified 747. Since that time we have had 42 flights with the aircraft. We have completed the passive optical testing of the aircraft. We have been actively lasing. In fact, this past weekend, we have gone through more than half of what we consider to be the full duration time for the laser. And, we have achieved a stable lasing and achieved equilibrium in the laser reactions.[18] So we have made tremendous progress. That portends to be a revolutionary capability with respect to defense and what it can add to this arsenal of defense against a ballistic missile threat.

ACT: You have already addressed it somewhat, but for decades missile defense and efforts to limit offensive missiles were viewed as competing against one another. How do you see the two as being complementary or how do you achieve that?

Obering: First of all, you have to recognize that arms control assumes rational actors. Arms control assumes adversaries that can be deterred. It assumes that there are people who have something to lose and that you can actually deal with in terms of negotiation and in terms of being able to come to an accommodation over a mutual disarmament, or even unilateral for that matter. What we are finding out today in this world is we have folks that are not like that. We have folks that are willing to sacrifice not only themselves but hundreds of people for a particular cause. If those people get their hands on these types of weapons—and there are hundreds and hundreds of missiles out there; many, many, many that are unaccounted for—they are almost undeterrable. Certainly, they are nonnegotiable when it comes to something like arms control. That is why I see us as being very much a collaborative effort. There are countries that can be deterred. There are countries that we can enter into arms control agreements with. I think that is very wise and that is something that we need to do. On the other hand, we have seen in the last several years that there are organizations and countries that just are not deterred in that manner.

ACT:Is there anything we have not asked about that you would like to add?

Obering: Just one of intent and one of what I will call trust. Many times you can get the feeling, if you read a lot of the critics of missile defense, that we are trying to pull the wool over somebody’s eyes or that we are trying to fool people or we are trying to build something that is unreliable or that is foolhardy. I wish that more people would give us the benefit of the doubt. We have thousands and thousands of dedicated Americans that are working very, very hard to build a defensive capability where there was none before. They are doing it for a very good reason. When you walk though some of the factories that we have that are producing these components and these systems, what you see on the walls are pictures of American cities. In many cases, they are aerial photographs of the hometowns of the workers that are crafting the system. They understand what they are doing is very important. I wish more people would give us the benefit of the doubt. We are on the side of trying to prevent weapons of mass destruction from being used against the American people and our interests. I think that is something that I would like to see emphasized much, much more.

ACT: Thank you very much for your time.



1. Ballistic missiles have three stages of flight: the boost phase, the midcourse phase, and the terminal phase. The boost phase begins at the missile’s launch and lasts until its rocket engines stop firing. Depending on the missile, this phase lasts between three to five minutes. The midcourse phase starts after the rockets finish firing and the missile is on a ballistic course toward its target. For ICBMs, this phase occurs in space and can last up to 20 minutes. It is during this stage that that the missile’s warhead(s) separate from the delivery vehicle. The terminal phase begins when the missile’s payload re-enters the Earth’s atmosphere and it continues until impact or detonation.

2. General John W. Holly, who oversees development of the ground-based midcourse defense, told a Washington audience Oct. 14, 2004, that the shakedown would take place over six to 12 weeks. (See ACT, December 2004.)

3. From October 1999 to December 2002, the Pentagon conducted eight missile intercept tests using the ground-based system. The system tallied five hits and three misses in these developmental tests.

4. The ground-based interceptors deployed at Fort Greely and Vandenberg Air Force Base are comprised of two main components: a high-speed booster and the EKV. The booster lifts the EKV into space, where the two then separate. Using radar updates and its own onboard sensors, the 70-kilogram EKV is supposed to maneuver into the path of an oncoming warhead and destroy it through a collision.

5. Global Hawk and Predator are unmanned aerial vehicles.

6. The GMD system is currently focused on intercepting targets traveling five to seven kilometers per second.

7. In these two tests, the interceptor failed to launch. (See ACT, March 2005.)

8. In all previous intercept tests, the targets have been fired from Vandenberg Air Force Base west over the Pacific Ocean toward the test interceptors based at Kwajalein Atoll in the Marshall Islands. By firing the targets from Kodiak Island and the interceptors from Vandenberg, the system will face new intercept trajectories.

9. The Aegis radar is part of a broader ship-based system originally intended to track and counter short- and medium-range ballistic missiles. In recent years, MDA has claimed the system can also help track a long-range ballistic missile. The concept is to use the ship-based radar to relay tracking data to a ground-based interceptor to help locate and engage a target.

10. Strategic systems are those designed to engage long-range ballistic missiles. Tactical or theater systems are those designed to counter short- and medium-range ballistic missiles. Different capabilities are needed to intercept missiles with different ranges because they all fly at varying speeds, trajectories, and altitudes.

11. North Korea ’s last ballistic missile flight test was an August 1998 test of its medium-range, 2,000-kilometer Taepo Dong-1. Although the U.S. intelligence community has assessed that North Korea is developing a longer-range Taepo Dong-2 capable of reaching the United States, Pyongyang has not tested such a missile.

12. Brilliant Pebbles was an initiative of President George H.W. Bush that envisioned up to 1,000 space-based interceptors.

13. At least the Czech Republic, Hungary, and Poland have all held discussions with the United States about hosting missile interceptors. (See ACT, July/August 2004.)

14. The Kinetic Energy Interceptor (KEI) is supposed to be a mobile land- or sea-based missile interceptor capable of traveling at some six kilometers per second. The interceptor was originally envisioned for taking out enemy missiles during the boost phase, but now MDA is exploring whether it might also be used to counter missile warheads in the midcourse phase. KEI is supposed to begin flight-testing in 2008 and the projected deployment date for the land-based model is 2013.

15. MDA does not fund the ground-based Patriot Advanced Capability-3 system against short- and medium-range missiles nor the Space-Based Infrared System-high (SBIRS-high), which is supposed to help detect missile launches worldwide. SBIRS-high is intended to replace the Defense Support Program satellites.

16. Formerly the Theater High Altitude Area Defense system, THAAD is a mobile ground-based system designed to intercept short-, medium-, and intermediate-range ballistic missile warheads near the end of the midcourse phase or the start of the terminal phase. Intercepts could take place inside or outside the atmosphere. THAAD was last flight-tested in the summer of 1999 after which it was put through a redesign.

17. The Airborne Laser program calls for mounting a powerful laser on a modified Boeing 747 to shoot down ballistic missiles in the first few minutes after their launch. During the Bill Clinton administration, Pentagon plans called for testing a completed system in 2003, but delays have postponed such an experiment until at least 2006.

18. Lasing is the process of creating the laser beam. It is estimated that the laser beam at full power would need to be concentrated on its target for a minimum of eight to 15 seconds to take it out. Currently, all 6 of the projected modules for creating a full power laser beam are currently being used in testing. The prototype laser, including its power producing modules, has yet to be integrated on the Boeing 747 aircraft.