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ACA Senior Fellow Talks Missile Defense at Penn State
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Siren Song: Strategic Missile Defense

Prepared Remarks by Greg Thielmann, Senior Fellow, Arms Control Association
Penn State University
March 3, 2011

Most of you in this audience will recognize sirens as mythical creatures from the Greek classics, dangerous bird-women, who lured passing sailors with their enchanting voices to shipwreck on the rocky shore.  Here is the encounter of Odysseus.  Warned in advance, Odysseus had his men stuff wax in their ears and had himself bound to the mast so that he could hear the sublime singing without dooming his crew to destruction.  Those with a more Germanic bent may visualize the maiden depicted by Heinrich Heine in his famous poem “Die Lorelei” -- Ihr gold'nes Geschmeide blitzet, and so forth.   The message is the same.  The girl’s face and voice are lovely, but if we don’t take our eyes off her and pay attention to the rocks, we’re all going down.  That is the thrust of my message today with regard to strategic missile defense – a siren song of our era.

Short Course

Before making my case, let me provide some context with a crash course on the weapons we’re talking about and a short review of the arms control treaties that have been reducing our bloated nuclear arsenals from their Cold War peak

First, The Weapons

Strategic offensive missiles are the ICBMs and SLBMs that can be launched from Russia to deliver nuclear warheads to the continental U.S. or vice versa, traveling 5,500 km in some 30 minutes.  The United States has only one missile defense system today that is designed to intercept such weapons, the Ground-Based Interceptor.  The so-called “GBI.” is a large multi-stage missile that destroys an incoming warhead by crashing a refrigerator-sized kill vehicle into it at extremely high speed.  The interceptor is guided by a variety of sensors -- one on the missile itself and others on satellites in space and in radars on the ground, like the Sea-Based X-Band Radar.  By 2020, current plans call for the U.S. to deploy a second type of interceptor missile, which can destroy ICBMs, the Aegis SM-3 IIB.  The other missile defense systems you read and hear about are for tactical or theater threats; they do not offer a means to defend against ICBMs.

Now, the Treaties

Less than one month ago, a new Strategic Arms Reduction Treaty, called “New START,” entered into force between Russia and the United States.  This was the latest way station on the long and rocky journey toward a safer and saner world.  Some would say the journey began in 1963 when the U.S., Great Britain, and the Soviet Union signed a treaty banning the testing of nuclear weapons in the atmosphere (LTBT).  That historic milestone was reached shortly after the world came to the brink of the abyss in the Cuban Missile Crisis of 1962.  It also followed the circulation of reports showing that fission bi-products from atmospheric nuclear testing, such as Strontium 90, were showing up in mother’s milk and baby teeth, all over the world.   Others would point to the 1968 nuclear Non-Proliferation Treaty (NPT) as the starting point.  This treaty required the five countries which then had nuclear weapons to start getting rid of them and the states which did not to forego the nuclear option.  While both of these treaties are in New START’s “family tree,” the first binding bilateral limit on strategic arms was the 1972 Interim Agreement coming out of the Strategic Arms Limitation Talks, and known as SALT I.  The parent of New START is the first Strategic Arms Reduction Treaty (START I), signed in 1991 by President George H.W. Bush and Soviet President Mikhael Gorbachev.  This treaty marked the first time the sides had agreed to specific numerical reductions in their strategic arsenals, to be accompanied by on-site inspections.

…and the Dead Ends

The journey to New START has also been marked by some detours and dead-ends.  The Carter Administration’s intention of ratifying the SALT II agreement of June 1979 became politically untenable once the Soviets invaded Afghanistan a few months later.  The START II agreement reached in 1994 was ultimately doomed by George W. Bush’s withdrawal from the Anti-Ballistic Missile Treaty (ABM), which had been in effect for 30 years.  And then there was the 2002 Moscow Treaty (aka SORT).  Although this treaty was ratified, it was deeply flawed, lacking verification provisions, a definition of the items being limited, a timetable for reductions, and durability.  (It was, in fact only scheduled to last one day at the end of 2012.)  Good riddance to that one!

The Sound of the Siren

Throughout the long and arduous quest to reduce nuclear arsenals, the strategic defense siren has been singing.  In listening to that song – like the boatman on the Rhine or the heroes of Greek mythology – Americans have been diverted from the deep water channel that provides an eventual way out of our existential dilemma.  Moreover, our boat is taking on water, and may, even now, be heading for the rocks.

The most successful communicator for strategic missile defense was the 40th president of the United States, Ronald Reagan.  Here are some excerpts from his famous “Star Wars” speech in March 2003:

“…rely[ing] on the specter of retaliation, on mutual threat [is] a sad commentary on the human condition. Wouldn't it be better to save lives than to avenge them? Are we not capable of demonstrating our peaceful intentions by applying all our abilities and our ingenuity to achieving a truly lasting stability?

“What if free people could live secure in the knowledge that their security did not rest upon the threat of instant U.S. retaliation to deter a Soviet attack, that we could intercept and destroy strategic ballistic missiles before they reached our own soil or that of our allies?

”…isn't it worth every investment necessary to free the world from the threat of nuclear war?

“I call upon the scientific community in our country, those who gave us nuclear weapons, to turn their great talents now to the cause of mankind and world peace, to give us the means of rendering these nuclear weapons impotent and obsolete.

“… tonight we're launching an effort which holds the promise of changing the course of human history.”

Adding to the impact of these stirring words, the Pentagon later provided film footage of ballistic missile interceptors smashing into target warheads at incredible closing speeds, producing brilliant explosions against the blackness of space.  Commentators contributed the powerful metaphor of “hitting a bullet with a bullet.”  A lobbying organization called “High Frontier” offered animated videos showing U.S. x-ray lasers in space zapping swarms of warheads careening toward the American homeland.  These fantasy scenarios were picked up by the mainstream media and run whenever the subject of advanced missile defenses was in the news. When the Cold War deflated the perceptions of nuclear danger, the 1998 Rumsfeld Commission on Foreign Ballistic Missile Threats and a 1999 National Intelligence Estimate picked up the slack.   Each offered shrill warnings about the rapidly growing ballistic missile threat to the United States and its allies from “rogue” states.  And for a quarter century, a cheering squad of missile defense enthusiasts has been nourished by Congressional appropriation of some $5-10 billion/year to universities, research labs, and weapons manufacturers.

Physics Lesson

I think it’s now time in my narrative to impart a few observations about rocket science and physics.  The first technical challenge with strategic missile defense is related to the extremely high velocity of warheads once the propulsion phase ends.

Intercontinental ballistic missiles (ICBMs) or submarine-launched ballistic missiles (SLBMs) travel on a ballistic trajectory like an artillery shell.  Their “boost phase,” when the rocket engines are firing, lasts only 5-7 minutes.  Then, the warheads’ carrier, or “bus” separates from the large booster stages.  At burnout, the ICBM warheads are traveling 7 kilometers per second through the void of space—much faster than shorter-range ballistic missiles that have been deployed by the North Koreans and Iranians.  ICBM warheads are therefore much harder to intercept.  They even travel faster than the defensive missile interceptors stationed in Alaska and California.  With our current system “architecture,” we would probably get just one chance to look and shoot, before it was too late.

As the warheads travel through the mid-course phase in the vacuum of space, they are relatively small and have no heat signature, which could otherwise reveal their presence to infra-red sensors.  So very powerful radars must be used to detect and track these objects from thousands of kilometers away.  These very expensive and huge tracking radars themselves become very lucrative strategic targets in a crisis, because their destruction renders the entire missile defense system ineffective.  The U.S. system relies heavily on the Shemya radar located in Alaska’s Aleutian Islands chain and a sea-based X-band radar floating off Alaska in the North Pacific.  Whether or not they can survive at the outset of hostilities is a largely ignored issue.  Moreover, in a nuclear conflict, the radars’ performance can be significantly degraded by detonating a nuclear explosion in the atmosphere.

But the real glass jaw of strategic missile defense comes from the ease of spoofing the sensors.  The “bus” carrying the warheads can emit a cloud of chaff (composed of highly-reflective foil) as it releases one or more warheads so that the exact location of actual warheads is obscured. The bus can also deploy decoys (basically, mylar-coated balloons) along with the warheads.  During the warheads’ flight through space, most of their flight time, these decoys look the same as actual warheads to the radar.  There is much open testimony over the years about their effectiveness from those involved in designing ways to defeat Moscow’s strategic ballistic missile defense system in the late 60s and 70s.  There has been almost no operational testing of the current systems’ ability to discriminate warheads from decoys.

As if the problem were not difficult enough, the offense has another trick up its sleeve to defeat the defense. The warheads can be made to maneuver.  So to return to the earlier metaphor, it’s even harder to hit a bullet with a bullet when the first bullet starts to bob and weave.  Even though the U.S. has conducted flight tests with maneuverable re-entry vehicles, known as “MaRVs,” we never actually deployed any because other penetration aids were judged sufficiently effective.

My bottom line:  Missile defenses against ballistic missiles with conventional warheads may, in certain situations, contribute to national security, whether they are 20% or 80% reliable.  Missile defenses against nuclear-tipped intercontinental range ballistic missiles are worthless in deterring attack – think about “only” 20-40% of nuclear warheads getting through -- and disastrous in curbing the arms race.

The U.S. defense community has not been deaf to the lure of the siren song, but through most of the Cold War, it ultimately turned away.  It first gave up trying to protect the U.S. population from a deliberate Soviet missile attack, changing the mission of its ABM in the mid-sixties to protecting against a deliberate Chinese or accidental Soviet launch.  Then in the late-sixties it gave up population defense entirely by deploying interceptors around ICBM fields.  This was done in the hope of strengthening deterrence by affecting the exchange ratio in the Soviet calculus – how many attacking warheads would be needed to attack warheads in silos.  Finally, the U.S. won limits on the number and location of strategic defense radars and interceptors through the 1972 ABM Treaty, completely banning systems designed to provide ballistic missile defense of national territory.  The Pentagon and Congress later judged that even the U.S. ABM system allowed under the treaty was not worth the effort, and closed it down after only a few months of operation.  Indeed, it ultimately abandoned President Reagan’s “Star Wars” fantasy because Special Advisor Paul Nitze’s criterion could not be satisfied -- missile defense systems would have to be “cost effective at the margin,” meaning that they made no sense if an enemy could more cheaply counter a missile defense interceptor by adding an additional offensive warhead.

But alas, our ship of state did not make it free to open waters.

--  Spooked by a North Korean missile launch, the U.S. Congress passed the 1999 Missile Defense Act, which provided the legislative imprimatur to deploying a strategic missile defense system to defend U.S. territory against limited attack (whether accidental, unauthorized, or deliberate)…”  Senate passage was almost unanimous; the House bill passed by a ratio of more than 3 to 1.

--  In 2001 President George W. Bush announced U.S. withdraws from the ABM Treaty, which had served for 30 years as a linch-pin of strategic arms control.  Previous UN General Assembly voting had shown strong international support for retention of the treaty.

-- At Bush’s direction, the Pentagon rushed to deploy strategic defenses in Alaska and California by 2004, even before they had been operationally tested.

--  This Alaska- and California-based system remain largely irrelevant in defending against the huge potential intercontinental ballistic missile threat we face today (from Russia and China).  And the threat against which they were designed to defend is still not even on the near horizon, seven years after deployment.

--  The new Strategic Arms Reduction Treaty acknowledges in its preamble the interrelationship between strategic offences and defenses, but the treaty text itself remained missile-defense-friendly – leaving U.S. missile defense plans unaffected and papering over a significant difference between the parties on the impact of strategic defenses.

-- The Senate’s Resolution of Ratification decrees that there will be no negotiation on US missile defenses.

We have thus bought time for implementing New START as the next step in nuclear arms reductions, but we’ve made negotiating follow-on reductions virtually impossible until our divergent views on missile defense are reconciled.

The View from Moscow

Russian reactions to the New START treaty and the U.S. missile defense program are complicated and conflicted. Moscow appears satisfied that it can proceed safely with modest reductions in strategic offensive systems under New START and has accepted NATO’s stated intention to develop territorial missile defenses for Europe.

However, Russian officials continue to voice concerns about future improvements in U.S. missile defense systems, as they did in Russia’s unilateral statement to New START, warning against a “quantitative and qualitative” buildup.  Moscow has been dubious for a long time about U.S. portrayals of a potential strategic threat from Iran and North Korea – in public and in confidential dialogue with the United States.[1] Even after Russia’s acceptance of NATO’s offer to cooperate on missile defense, Russian Ambassador to NATO Dmitry Rogozin openly declared, “Russia does not see any missile threats in northern Europe, so the [US] defense systems should not be deployed there.”[2]

Moscow appears to accept the logic of U.S.-Russian cooperation on missile defense, but remains skeptical such cooperation could ever lead to a safe and truly equitable joint relationship.  Russia demands full equality in the control of any cooperative approach to missile defense.  According to Russian Defense Minister Serdyukov, “We also want to ensure that Russia participates as an equal partner. Only then can a missile defense system be created that satisfies all sides.”[3]

In spite of President Medvedev’s upbeat rhetoric about his conversations at the November 2010 meeting of the NATO-Russia Council, his emphasis on “absolute equality” and endorsement of a side-by-side “sector-based” missile defense system appear to go far beyond the evolving concept articulated by NATO.  In fact, Medvedev’s characterization of his discussions does not seem consistent with the territorial defense plan outlined by NATO.  Moreover, his emphasis on the interrelationship between European missile defenses and Russian strategic offenses gives little support for the notion of a fundamental change in Russian strategic thinking.  According to Medvedev: “…countries still have their nuclear forces in place today, and when we look at missile defence we have to look too at the possible effects a European missile defence system could have on our nuclear forces.”[4]

So why are the Russians so paranoid?  The Cold War is over.  We’re both threatened by those crazy people in Iran and North Korea.  Why not cooperate to defend ourselves against the real potential enemy?

The Limits of Cooperation

It is possible that disparate U.S. and Russian assessments of the Iranian threat will begin to merge if the threat grows – and that continually improving US-Russian relations will permit an unprecedented level of missile defense cooperation.  Yet, there is reason to question whether such efforts will bear enough fruit to satisfy Russia’s concerns about the potential long-term effect of U.S. strategic missile defenses on Russia’s deterrent.  Consider the view from Moscow.  The U.S. internal debate on New START revealed great sensitivity within the executive and legislative branches of the US Government to granting Russia access to telemetry involving missile defense flight tests.  (Congress prohibits it.)  The United States has made clear that cooperation does not mean building a “dual key” system, requiring the involvement of each side to operate.  Sergey Rogov, Director of Russia’s USA and Canada Institute, comments that: “Russia and the United States hardly are ready to agree to create a joint missile defense.”[5] Both sides would likely wish to retain their ability to operate missile defenses independently of the other. This independence might actually contribute to stability in a crisis because each side would be confident of the ability to control its own assets, but it would not foster arms race stability because suspicions of intent would linger.

The most compelling reason to believe that cooperation will be insufficient is to imagine the United States in a position similar to Russia’s today.  Remember that the U.S. Senate had trouble even consenting to a nuclear arms control agreement that leaves U.S. missile defenses unlimited.  Unlike past strategic arms reduction treaties, New START did not pass overwhelmingly, even though it was a very good deal for us.  (It requires only modest reductions in U.S. offensive forces; it leaves force structures allowing the US to dominate treaty breakout contingencies; and it requires intrusive inspections that provide the US with critical information on Russian strategic forces otherwise unavailable.)  To expect the Russians to accept additional reductions in their strategic offensive forces without constraining U.S. options for expanding strategic missile defenses is unrealistic.

The Enduring Reality of the Interrelationship Between Missile Offense and Defense

The nuclear age carries a consistent core message concerning the interrelationship between strategic missile offense and strategic missile defense: a defensive buildup creates pressures for offensive countermeasures – and in such a competition, offenses are likely to cancel out the intended benefits of the defenses.  The offensive response occurs for two reasons:  First, because of the obvious need to compensate for the potential degradation in target coverage that could result from the other side’s ability to intercept incoming warheads; And second, because the missile defense programs tend to arouse suspicions about motives.  When the Soviets started deploying missile defenses around Moscow in the 1960s, the US found it “intensely threatening to our security,” according to distinguished scientist and mathematician Freeman Dyson, writing in 1964, “The fear of Soviet ABM[s]…seems to be more deeply felt than the fear of Soviet offensive forces.… This logic …led many people … to consider the Soviet ABM program as primarily intended to allow the Soviet Union to attack the U.S. without fear of retaliation.”[6]

A contemporary reference to the offense-defense interrelationship can be found in September 2010 remarks of U.S. Strategic Forces Commander Gen. Kevin Chilton: “As we develop missile defense capability, we don’t want to develop it in such a manner that the Chinese would feel that their assured response, their deterrent, is put at risk, because that would encourage them to build more intercontinental missiles or capabilities.”[7]

More Shields; More Swords

Although many missile defense advocates contend that missile defenses discourage the proliferation of offensive missiles, empirical evidence shows just the opposite.  Missile defense systems encourage opponents to hold on to their offensive missiles or create more of them.  This is what happened with the U.S. response to the Moscow ABM system in the 1960s; with the Soviet Union’s response to Reagan’s “Star Wars” in the 1980s; with China’s response to Taiwan’s deployment of Patriot anti-tactical missile defenses in the 1990s.  During the last decade, Iran’s considerable build-up of medium-range missiles has occurred in the face of Israel’s extensive build-up of missile defenses; Pakistan’s continuing build-up of nuclear tipped missiles has occurred as India launched its own missile defense effort.

The end of the Cold War and rapprochement between the US and Russia have helped convince the last four U.S. Administrations to alter the original mission of missile defense.  Instead of protecting against a catastrophic potential attack from Russia, the current objective is to protect against much more limited threats from “rogue” states.[8] Technical and budgetary obstacles have kept a lid on some of the more fanciful visions of the Reagan administration regarding lasers, particle-beam weapons, and space-based systems, narrowing the focus to more down-to-earth capabilities such as the GBI missiles currently deployed and a souped-up version of the SM-3 theater system (the Block IIB) that would give it anti-ICBM capabilities.  This system is in early development and is planned for deployment in 2020 under President Obama’s European Phased Adaptive Approach.  [Slide 5] Both systems are likely to be in the spotlight during negotiations of a post-New START agreement.

Some, like former Secretary of State Condi Rice, believe that the offense-defense dynamic was broken by U.S. withdrawal from the ABM Treaty in 2002.[9] Yet, this interrelationship cannot be severed by unilateral action or simply dismissed as an attribute of the Cold War, for it flows not from history or treaty language, but from physics and psychology.

The governments in Washington and Moscow, which control the vast majority of the world’s long-range ballistic missiles, demonstrate today the same dynamic on strategic missile defense they have demonstrated for decades.  One side pursues a major missile defense program; the other side seeks to limit it through negotiations and mitigate its impact through improvements in its own offensive forces.  However, there is one major difference: Moscow and Washington have changed sides.

The Siren Song Surges

During a long period of equilibrium under the conceptual foundation of the ABM Treaty, the sides were able to cut in half their huge offensive arsenals.  But the siren song surged and safe passage around the rocks is again threatened.

Following passage of the Missile Defense Act of 1999 and U.S. withdrawal from the ABM Treaty three years later, the conventional wisdom appears to have hardened around the notion that missile defenses should forever remain outside the arms control realm.  The 2010 elections would appear to have increased congressional determination to reject any limits on missile defenses. Changes in the New START resolution of approval constitute evidence of increased Senate resistance to such limits.

If we want further reductions in nuclear weapons and better protection against them spreading to other countries, we need to tone down or tune out the siren song of strategic missile defense.

One Approach

One approach to tackling this dilemma would be simply to create a strategic missile defense interceptor limit in parallel with limits on offenses, for example, reducing to a ceiling of 1,000 strategic offensive warheads and 100 strategic defense interceptors. The limit also could be geographical because the vulnerability of Russian ICBMs to interception by SM-3 IIBs would be affected significantly by the location of deployments.  Limits on the number deployed near Russia’s borders would be superficially similar to the numerical and geographical limits on strategic ABM interceptors in the ABM Treaty.  But the purpose of that treaty was to prevent the deployment of nationwide strategic ballistic missile defenses, principally through qualitative limits on radar construction.  Breakout potential then was controlled further by quantitative limits on strategic interceptors—200 in the original treaty, lowered to 100 in 1974—and by clearly demarking the performance characteristics of strategic and nonstrategic interceptors as was done in a 1997 agreement.[10]

In contrast to their position when the ABM Treaty was in force, the Russians now have conceded the principle of permitting nationwide strategic ballistic missile defenses.  They acknowledged in New START’s preamble that “current defensive arms do not undermine the viability and effectiveness of the strategic offensive arms of the parties.”  Indeed, the number of strategic interceptors that were allowed even under the amended ABM Treaty was much higher than the number of U.S. ground-based strategic interceptors deployed today and it’s probably in the vicinity of the number needed for the US to cope with likely contingencies from Iran and North Korea in the 2020s. Even after adding the upgraded SM-3 IIB systems envisioned for the end of the decade under Obama’s plan, total numbers still would be within the limits on strategic missile interceptors last enumerated in the ABM Treaty.  In 1997, Russia agreed that the performance of the original SM-3 and Terminal High Altitude Area Defense (THAAD)  interceptors were “non-strategic” and therefore should not create an obstacle to continued reductions in strategic nuclear forces as they become operational over the next five years.

We need to begin opening up a public dialogue on the real-world opportunity costs of opposing all missile defense limits. This dialogue should extend to U.S. NATO allies in Europe and the Pacific who directly face shorter-range ballistic missile threats from hostile states.  Let’s check this out.  Consider whether you would be able to answer yes to each of these questions:

-- Is a highly reliable missile defense potential likely to be affordable in the decade ahead, even assuming that it is technically achievable?

-- Is the value of unconstrained U.S. strategic missile defenses superior to the value of achieving additional reductions in Russian strategic offensive systems and of adding strategic nondeployed and tactical systems to the list of weapons to be cut?

-- Is keeping missile defenses unconstrained worth risking the chance of limiting the growth in Chinese strategic forces?

--  Indeed, can one even contemplate successful pursuit of nonproliferation if efforts to stem vertical proliferation grind to a halt as a result of missile defense deployments?

Unless we can confidently answer “yes” to each of these questions, it’s time to consider realistic alternatives to unconstrained growth in strategic missile defenses.  Put some wax in your ears to block out the siren song and let’s head for open water!


[1] A February 24, 2010, Department of State cable, released by WikiLeaks, reporting on December 22, 2009, talks on missile threat assessments between U.S.-Russian delegations in Washington revealed significant differences in the two countries’ official, classified assessments of Iranian and North Korean ballistic missile capabilities.

[2] Mikhail Fomichev, “European Missile Defense System Either With Russia or Against Russia – NATO Envoy,” RIA Novosti, December 2, 2010.

[3] “Moscow Wants to ‘Participate as an Equal Partner,’” Der Spiegel, October 27, 2010.

[4] Ibid.

[5] Sergey Mikhaylovich Rogov, “The ‘Window of Opportunity’ Is Open,” Nezavisimoye Voyennoye Obozreniye, May 28, 2010.

[6] Freeman J. Dyson, “Ballistic Missiles,” Bulletin of the Atomic Scientists, June 1964, p. 18.

[7] Gen. Kevin P. Chilton, “Nuclear Deterrence, START, Arms Control, Missile Defense and Defense Policy,” Presentation at the NDU Foundation Congressional Breakfast Seminar Series, September 13, 2010.

[8] A small but increasingly influential minority of missile defense advocates, such as Senators Jim DeMint (R-S.C.) and James Inhofe (R-Okla.), have explicitly called for broadening the objectives of missile defense to include providing territorial defense against Russia and China.

[9] See, for example, Condoleezza Rice, “New Start: Ratify, With Caveats,” The Wall Street Journal, December 7, 2010.

[10] The “New York Agreements on Theater Missile Defense and ABM Treaty Successor States,” signed by the United States, Russia, Belarus, Kazakhstan, and Ukraine on September 26, 1997, included two “Agreed Statements on Demarcation,” identifying 3 kilometers per second as the critical performance parameter separating prohibited “higher velocity” theater missile defenses from permitted “lower velocity” theater missile defenses. For the text of the agreements and statements, see www.fas.org/nuke/control/abmt/text/abm_scc1.htm and www.fas.org/nuke/control/abmt/text/abm_scc2.htm. For a summary of the agreements and statements, see