The coronavirus crisis is a reminder that catastrophes sometimes befall civilization with little or no warning. U.S. policymakers can be forgiven for not realizing how quickly the virus would spread, but they have had plenty of warning about other dangers that could cause widespread suffering.
Foremost among these is the threat of nuclear attack. A single nuclear warhead aimed at a major U.S. city could kill more Americans than all 675,000 men, women and children lost during the Spanish flu outbreak of 1918 (the worst pandemic on record).
Recognizing the danger, Washington is modernizing every part of its strategic arsenal to assure deterrence of nuclear aggression by Russia or China. However, other nuclear actors such as North Korea are emerging that may not be deterred by the threat of massive retaliation.
The only real solution Washington has to cope with threats from such rogue states—Iran’s future behavior looks unpredictable as well—is to build active defenses of the American homeland. The word “active” in this context means being able to track and intercept nuclear warheads approaching U.S. territory, rather than merely threatening retaliation.
The Missile Defense Agency has been gradually increasing THAAD capabilities since its inception.
Unfortunately, the complexity of nuclear threats posed by North Korea is increasing. Among the concerns troubling U.S. policymakers are that Pyongyang might steadily increase the number of long-range missiles in its arsenal; develop penetration aids that confuse U.S. defenders; or place multiple warheads on each missile that overwhelm existing defenses.
Overwhelming homeland defenses wouldn’t be hard today, because there are only 44 interceptor missiles in the entire U.S. arsenal designed to defend against warheads delivered by long-range missiles. Up to four might be needed to counter each incoming warhead.
Policymakers have concluded that the nation needs more robust missile defenses, including a Next Generation Interceptor, a resilient battle management network, and a layered architecture. The logic of layering is straightforward: if there are two lines of defense and each one can destroy 80% of incoming warheads, then only 4% of the warheads will reach targets in the U.S. If the attack consists of two dozen warheads, only one and possibly none will get through.
We already know what the first layer of defense will be that destroys warheads while they are coasting through space towards America. Initially it will be the interceptors already deployed in the existing Ground-based Midcourse Defense, later it will be the Next Generation Interceptor. Dr. Michael Griffin, the Pentagon’s top research official, thinks the new interceptors can be available by midway through this decade.
But what about the second layer of defense that must destroy the remaining warheads in an attack that has already been thinned out? What weapons are suitable for intercepting attacking nuclear warheads as they approach their all-too-aptly named “terminal” phase?
Only two options appear readily available. One is the Aegis defense system deployed on U.S. Navy warships. The other is the land-mobile Terminal High Altitude Area Defense (THAAD) originally begun by the U.S. Army and now managed by the Pentagon’s Missile Defense Agency.
Both systems are built by Lockheed Martin in conjunction with other contractors such as Raytheon and Aerojet Rocketdyne. I have relationships of one sort or another with many of the companies involved, so I occasionally get briefed on the state of play.
The bottom line is that both Aegis and THAAD are currently capable of intercepting intermediate-range ballistic missiles and those with shorter ranges. If they are going to provide the second layer in a homeland defense system, as the Missile Defense Agency apparently contemplates, they will need to be evolved.
That process has already commenced, and indications are that both have the potential to intercept long-range warheads approaching the U.S. at hypersonic speeds (a mile per second or faster). The plan is to track hostile warheads with such precision that interceptor missiles can physically collide with attackers, generating so much kinetic energy that the incoming warhead is effectively vaporized.
This capability has been successfully demonstrated many times, but usually against targets with less-than-intercontinental range. So the systems will need to be upgraded to assure their reliability against the emerging threat to America’s homeland posed by countries like North Korea.
Continued enhancement of the Navy’s Aegis system is a no-brainer since it has been steadily improved since it was first deployed decades ago; it is the most survivable component in the U.S. missile defense system, and its tracking radars are already tied into the homeland defense architecture.
THAAD presents a separate opportunity for rapid improvement, thanks in part to the Kingdom of Saudi Arabia. In 2017 the Trump Administration approved sale of seven THAAD batteries to the kingdom so that it could defend itself against an Iranian missile attack. That work, combined with funding in the 2021 Pentagon budget request, potentially provides a fast and affordable path for making THAAD relevant to homeland defense.
In fact, it may be relevant today. The system has at least some inherent potential for intercepting warheads delivered over intercontinental distances. What is needed is to keep evolving THAAD so it can fly farther and faster in countering hostile warheads. In addition, the system needs to be tied into the homeland defense architecture rather than treated mainly as a regional defense system.
The Missile Defense Agency’s decision to use THAAD in defense of Hawaii underscores that it is more than simply a regional defense solution. It can be used to defeat intercontinental ballistic missile warheads, and even maneuvering hypersonic warheads. It wasn’t originally conceived for those purposes, but work on evolving the system by the Missile Defense Agency and contractors has given it that potential.
As THAAD evolves, it will be able to address a wider array of threats to the U.S. homeland and overseas allies. The important thing in the near term is to leverage funding synergies generated by the Saudi sale to help develop a second layer in the homeland defense architecture. That should include early testing of THAAD against targets that mimic the characteristics of long-range warheads.
The nation needs a layered missile defense, because someday soon the coronavirus pandemic will be over, but the nuclear threat from rogue states will continue growing. The Terminal High Altitude Area Defense is one of the few options Pentagon planners have to keep up with a rapidly evolving threat to America’s homeland.
THAAD lead contractor Lockheed Martin contributes to my think tank and is a consulting client.
