Abstract
Taking aim at missile defense
With regard to the excellent article by George N. Lewis and Theodore A. Postol, (“The European Missile Defense Folly,” May/June 2008 Bulletin), it's worth noting that the U.S. Missile Defense Agency (MDA) has told Congress and the media that it can only handle “an unsophisticated threat,” that is, just one or at most two missiles from Iran (or North Korea), with no decoys or countermeasures.
Yet it's not credible that Iran (or North Korea) would be reckless enough to attack Europe or the United States with a single missile–without decoys or countermeasures–and then sit back and wait for the consequences. As we know, ballistic missiles have return addresses. If Iran were reckless enough to attack Europe or the United States, it would launch several missiles or use decoys and countermeasures, in which case current U.S. missile defenses wouldn't be effective.
Further, if Iran or North Korea were intent on attacking Europe or the United States, and if they believed that U.S. missile defenses worked, they likely would emulate Russian strategy. Against Russian or Chinese intercontinental ballistic missiles launched en masse, even the most futuristic missile defenses wouldn't be effective. Congress recognized this in 1974, when it voted to shut down the Safeguard antiballistic missile system (which relied on nuclear-armed interceptors) almost immediately after it was declared operational because it was obvious that the system couldn't defend against an all-out Soviet attack.
The world will not be safer if U.S. missile defenses cause Iran, North Korea, or other countries to build up vast arsenals of ballistic missiles to overwhelm them. In this way, U.S. missile defenses create new dangers for America, stimulating a new arms race and encouraging adversaries to build more and more missiles so as to overwhelm U.S. defenses. By responding to the perceived “unsophisticated threat,” the United States is motivating new threats for which it doesn't have technical solutions.
Senior adviser
Center for Defense Information
Washington, D.C.
“The European Missile Defense Folly” once again demonstrates that two fundamental and unavoidable problems dog defenses against long-range missiles. It seems that physicists will have to explain these problems over and over again as penance for having invented nuclear weapons. After all, the idea of defending against nuclear-armed missiles is very compelling.
First, “It's the countermeasures, stupid.” The United States and the Soviet Union recognized this problem in the 1960s, and thereby negotiated the Anti-Ballistic Missile Treaty to limit missile defense systems. Technology has vastly improved since then (instead of using nuclear-tipped interceptors, the planned U.S. system uses hit-to-kill interceptors), and it hasn't made a whit of difference. As George Lewis and Theodore Postol discuss, any defenses designed to intercept long-range missiles outside the atmosphere–where there is no air and hence no air-resistance–will be vulnerable to simple lightweight decoys that will travel on the same trajectories as a heavy warhead. (There are other countermeasures to defenses designed to intercept these missiles during boost-phase.)
Second, any nation seeking to maintain a deterrent relationship with the United States will assume the worst–namely, that the system will work as intended. Of course, this will lead the other country to take compensatory steps–perhaps adding warheads or maintaining existing warheads on high alert–that are inherently dangerous. Perhaps worse, it will lead to political tensions, as we see now in Russia's reaction to U.S. plans to expand its defense to Europe. The United States should be leading efforts toward a world without nuclear weapons, and such tension blocks any efforts in this direction.
I remain hopeful that the next administration will give the physicists a reprieve in their Sisyphean task, cancel the missile defense program, and take needed steps to move the world toward zero nuclear weapons.
Union of Concerned Scientists, Boston, Massachusetts
George Lewis and Theodore Postol admirably uncover the frailties of the radars intended to work with the proposed U.S. missile defenses in Europe. They mention that “highly accurate ‘cuing’ information from the FBX [forward-based X-band] radar, the Fylingdales radar, and the early warning satellites is essential if the defense is to work as intended.” They are absolutely correct. What should be noted is that none of those programs has been completed and proven to work in the capacity that the Missile Defense Agency plans on using it. The Fylingdales radar is still being upgraded. Neither the FBX nor any other radar has guided an interceptor using constantly updated, real-time data during an entire test attempt, and the satellite networks needed to detect missiles as they are launched and track them throughout their trajectories are behind schedule and over budget.
A significant component of the proposed system for Europe also remains absent: the interceptor. The Pentagon plans to use a modified version of the ground-based midcourse defense (GMD) as the system's interceptor. Yet it doesn't anticipate testing this variant until mid-2010 at the earliest. Seeing as how the GMD interceptor has, after nine years of testing, made interceptions in only seven out of thirteen attempts, it may be a while before its variant demonstrates reliability.
It's important to step outside of the politics of missile defense and take a good hard look, as Lewis and Postol did, at the realities of the technologies involved.
Research analyst
Center for Defense Information
Washington D.C.
“The European Missile Defense Folly” as presented by George Lewis and Theodore Postol is based on opinion and what they think they know about the technical aspects of the planned location of U.S. missile defense assets in Poland and the Czech Republic. Postol and Lewis conducted their analysis from the outside looking in and did not have access to protected technical information that would have allowed them to truly evaluate and understand current missile defense system performance.
Their assertion that “basic counter-measures will topple the system” may have been correct based upon the level of technology they were familiar with 10-20 years ago, but it doesn't apply today. Advances in sensors, seekers, radars, and discrimination technology give Missile Defense Agency (MDA) officials a great deal of confidence that the current long-range missile defense element has the capability to defeat simple countermeasures. Also, we have an extensive targets and countermeasures development effort under way to ensure we can meet future threats. An example is the Multiple Kill Vehicle program, which will allow MDA to deploy several interceptor kill vehicles aboard a single missile to destroy a wide variety of threat objects, including the lethal warhead and any countermeasures traveling with it.
Postol and Lewis's analysis also disregards the role other sensors and radars play in discrimination. It looks only at the performance of the interceptor kill vehicle sensor when assessing countermeasure effectiveness. Yet the U.S. capability against countermeasures is significantly greater considering that it employs layered defenses with a redundant network of highly effective land- and sea-based sensors, as well as advanced discrimination algorithms.
Postol and Lewis assert that the X-band radar proposed for deployment in the Czech Republic is “substantially underpowered” and thus ineffective. This is simply wrong. The sensitivity of the radar has been demonstrated, documented, and verified in 38 flight-tests since 1998. The Pentagon's director of operational test and evaluation called it “excellent” in a report prepared last fall. The radar provides very high signal strength regardless of warhead orientation and is more than sufficient to perform its mission against a ballistic missile threat from Iran. The radar will be upgraded with faster data-processing capabilities that will make it even more effective.
Postol and Lewis also assert that a radar now located in Norway will be used as part of any European missile defense deployment. The United States has no plans to incorporate this radar into the ballistic missile defense system, and this has been stated time and again for nearly a decade.
Finally, Postol and Lewis state what can only be considered a total contradiction. They argue the operational performance of the system cannot be effective against Iran's long-range missile now in development but then assert that the system will be so effective as to threaten Russia's more advanced intercontinental ballistic missiles. They also make overly optimistic assumptions regarding booster performance and the generation of trajectories; they assume a faster interceptor burnout time and a much shorter system reaction time than we estimate to be possible. Additionally, there is absolutely no plan to field more than 10 interceptors in Poland, because this is the number we feel is necessary to meet the expected threat.
The Defense Department is actively engaged in developing more capable mobile systems–the high-acceleration kinetic energy interceptor, the sea-based SM-3 Block IIA interceptor, and the airborne laser–to provide a layered defense to meet what will likely be more sophisticated threats in the future from countries such as Iran and North Korea, and we will work closely with our NATO partners, as well as with Russia and other nations, to address these threats.
U.S. Missile Defense Agency, Washington, D.C.
Lehner would have you believe that the capabilities of the European mid-course radar, which has a well-known unclassified power and aperture, can identify the differences between distant warheads and decoys hundreds of times better than the performance limits set by electromagnetic theory and the law of conservation of energy. He further claims that new “sensors, seekers, radars, and discrimination technology” allow the MDA to obtain information that doesn't exist in the signals they measure and analyze. Of course, to understand why these claims are true, you need to know what he knows, and he can't tell you, because it's all secret.
To understand why Lehner's claims about improved sensors and algorithms are neither secret nor true, consider the problem of finding suitcases that contain bombs at an airport. In the case of missile defense, all of the sensors, seekers, and radars that are a part of the system are limited to seeing only the surface characteristics of the objects they observe. At an airport, the equivalent “sensor systems” would only see the outside of the objects of concern, i.e., they'd be limited to visual inspections of suitcases.
Improvements in visual sensors might allow them to better measure the color and surface texture of pieces of luggage, and improved algorithms might be able to infer from the visual data characteristics of surface materials. However, none of the information in the observed “signals” and none of the insights produced by the improved algorithm would contain any information about whether the suitcase contains a bomb.
Yet, Lehner claims that the MDA has the capability to tell whether a bomb is “inside the suitcase” (i.e., the missile) because the MDA has made improvements to its visual sensors and algorithms.
More recently, now-retired Lt. Gen. Henry A. Obering expanded these amazing assertions in testimony before the House Subcommittee on National Security and Foreign Policy on April 30, 2008. He asserted, under oath, that the European missile defense system would soon be able to discriminate against advanced Russian countermeasures. Yet Obering's testimony carefully avoided talking about the only two integrated flight tests that tested the discrimination capabilities of the current missile defense system, the IFT-1A, performed in June 1997, and the IFT-2, performed in January 1998.
Instead, the focus of recent MDA testimony has mysteriously switched to a series of missile defense tests since 1998 that were aimed at determining how well the ground-based missile defense systems could hit well-identified targets. These experiments, which were not intended to test the discrimination capabilities of the missile defense system, are now cited as evidence that the system is “more than sufficient to perform its mission against a ballistic missile threat from Iran,” as Lehner claims in his letter.
We think it's time for Congress to exercise its oversight authority on the MDA. It should begin by reviewing why the MDA no longer acknowledges the early claims that the IFT-1A and IFT-2 experiments were unqualified successes in demonstrating that the current missile defense system can discriminate between warheads and decoys. Congress should also investigate why experiments that were explicitly designed to test only whether the ground-based missile defense can hit a well-identified target have been substituted in their place.
The MDA's shenanigans shouldn't be allowed to continue when the country is faced with enormous military and economic challenges. Though it's unlikely to happen, people like Lehner and Obering should be deposed under oath so Congress can determine whether or not they've been telling the truth during the years they have been speaking for the MDA.
ENERGY WITHOUT PROLIFERATION
Reintroducing the conclusions of Hans Bethe's prescient Bulletin essays on nuclear energy in “Talking About Nuclear Energy” (May/June 2008 Bulletin) reminds us that the problems associated with nuclear power–namely proliferation, waste disposal, economics, and safety of operation–have not changed much. But since Bethe's time, parallel energy, climate, and proliferation crises have emerged that call for a reexamination of nuclear power as a source of safe, reliable, and economically attractive energy.
Talk of nuclear power almost exclusively focuses on uranium-based fission schemes. But a viable thorium fuel cycle, where thorium 232 is irradiated to create fuel in the form of uranium 233, could all but eliminate the proliferation threat and result in safer operation. This could allow nuclear to serve as a base-load energy-generating buffer while we develop alternative and renewable energy sources.
Considering its potential advantages, it's perplexing that the thorium fuel cycle wasn't mentioned in Robert Rosner's “Making Nuclear Energy Work” (March/April 2008 Bulletin) as a candidate for computer-aided research and experimentation, because it may mitigate some problems inherent to the uranium cycle.
Thorium oxide is more chemically stable than uranium oxide (having a higher melting point), allowing safer reactor operation. Thorium is also widely distributed in Earth's upper crust and is four times more abundant than uranium. The thorium fuel cycle is intrinsically proliferation-resistant due to the presence of a small amount of highly radioactive uranium 232 in uranium 233 fuel that makes it too difficult to handle for a bomb or for would-be thieves to steal. Moreover, mixed-oxide fuel made with thorium and weapons-usable plutonium left over from the traditional uranium fuel cycle incinerates more plutonium than the more conventional uranium/plutonium mixed-oxide fuel cycle does.
Problems with the thorium fuel cycle include depleted fuel management and processing of fission products, but these issues may be tractable by applying technology developed for uranium reactors to the thorium fuel cycle. Also, radioactive waste products from the thorium fuel cycle have a shorter half-life than the uranium or plutonium cycles, mitigating long-term storage problems. A key question that could be answered using experiments and computer modeling is whether current and newly designed nuclear plants can be redesigned to accommodate the thorium fuel cycle. If so, there is no excuse to stick with a fuel cycle that involves enriching large quantities of uranium 235 and produces plutonium 239 as a waste product. Both elements can be readily used to produce nuclear weapons.
Effectively transitioning the nuclear industry over to the thorium fuel cycle may make nuclear power work in the best collective interests of international peace and security, long-term economic sustainability, and environmental preservation.
Departments of Astronomy and Earth and Planetary Sciences
Department of Earth and Planetary Sciences, harvard University
THE CLIMATE-CONFLICT CONNECTION
In “Climate Change and Security,” (May/June 2008 Bulletin) Jürgen Scheffran suggests that the impact of climate changes on water and food resources, natural disasters, and migration may induce warfare. However, a strong positive correlation doesn't exist, and without correlation, causality is questionable.
Environmental factors per se don't cause war any more than cold weather causes head colds. The root cause of violent conflict remains innate human aggression uncontrolled by a robust international legal framework.
If we want to live in peace, we must accede to international jurisdiction and establish an enforcement mechanism to regulate mankind's natural temperament.
Atlanta, georgia
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