The Sept. 11, 2001, attacks on the United States provided a dramatic warning that even the “world’s hegemon,” as America was called by some, was not invulnerable to threats against the homeland. As Americans, their elected officials, and the intelligence and military communities evaluated 21^st century threats, the assessment was clear. Absent terrorists operating on American soil, the one existential threat to the nation was the rapidly growing number of states and other actors who already possessed – or were developing – chemical, biological, and nuclear weapons of mass destruction (WMD) and who also possessed, or were developing, ballistic missiles to carry these weapons great distances. In the decade-plus since those 9/11 attacks, rogue nations such as Iran and North Korea have, in fact, developed and in some cases launched ballistic missiles, often designed to intimidate their neighbors.

For the nation, the military, and especially for the Navy, the need to develop robust defenses against this threat was as clear as it was compelling. Under the overarching stewardship of the United States Missile Defense Agency (and its predecessor agencies) this new emphasis accelerated ballistic missile defense development. Like the German buzz-bombs and Japanese Kamikaze attacks during World War II, Americans were reminded once again of the potential of missile attack from the air, both to forward-deployed forces as well as the homeland.

 

Early Navy Involvement

The Navy’s involvement in ballistic missile defense goes back a half-century. By the late 1950s the Navy knew the Soviet Union was deploying submarine-launched ballistic missiles, and by the early 1960s there was growing interest in defense against a growing Soviet ballistic missile threat. During this timeframe the Johnson Administration became interested in national missile defense, and the U.S. Army began working on a national missile defense system. However, this Army-dominated system was unlikely to be effective against submarine-launched weapons. It relied on long-range radars to warn of approaching intercontinental ballistic missiles.

But in 1972 the United States and the Soviet Union agreed to strategic arms limitation, including limiting defensive weapons. Each country was now allowed only two defensive systems, one of which could defend its capital. There was no longer a role for a sea-based segment. Indeed, there was no longer much of a future for the U.S. national system.

However, President Ronald Reagan revived the U.S. ballistic missile defense program in 1983 when he asked, in his now-famous speech; “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?” The national imperative to defend against ballistic missiles was reborn.

 

National Ballistic Missile Defense Emerges

In March 1983 Reagan announced a Strategic Defense Initiative (SDI) as a way of breaking away from relying on mutually assured destruction to defend the United States. Although he did not denounce the ABM Treaty, the available evidence suggests he envisaged that as soon as SDI technology became practical, the U.S. would no longer be part of this treaty. The Navy believed that the service could have a role in national ballistic missile defense, and conducted a study showing that the Navy could offer ships proficient in both ASW and missile defense to deal with the submarine-launched missile threat.

When the Berlin Wall fell in November 1989, a decision was made to rethink SDI. Eventually, the decision was made to reorient SDI from an attempt to defend the United States against mass attacks by a peer competitor, to defense against a smaller number of long-range missiles fired either accidentally or by rogue states or terrorist groups. It was envisaged that any program providing defense of deployed U.S. forces and allies would be partly sea-based. Importantly for the Navy, wartime events would show that the Aegis SPY-1 radar could be adapted to the problem.

 

The Ballistic Missile Defense Equation Shifts

The 1991 Gulf War demonstrated to Americans the compelling nature of theater ballistic missile threat. Scud missile attacks on Saudi Arabia were clearly intended to punish the Saudis for being the logistical key to any attack against Iraqi forces. When the SPY-1 tapes from Aegis ships deployed in the Gulf during the war were examined, the Scuds could be seen. It became clear that SPY-1 could have detected these Scuds. The revelation that the Navy’s premier anti-air system could also be its anti-ballistic-missile system inspired many to envision this new role for Aegis. Therefore, in the spring of 1991 both the Strategic Defense Initiative Office (a forerunner of the Missile Defense Agency) and Congress asked the Navy to explore ways in which it might create a sea-based form of defense against tactical and theater ballistic missiles, using the existing Aegis system as a basis.

The full story of how Navy BMD has evolved will be told later, but as indicated above, when the threat changed from massed ICBM attacks by a peer competitor to smaller attacks by rogue states or terrorist groups, the entire strategic, operational and tactical calculus of U.S. national BMD changed with it. The concept of operations for national and regional BMD is now focused on this more discrete threat. But while the threat is discrete, it is real – and growing.

 

The Ballistic Missile Threat Continues to Grow

One of the early – and compelling – calls for a prominent Navy role in dealing with the ballistic missile threat came over a decade ago in a little-noticed report issued by the U.S. National Defense University. Published in their occasional series Defense Horizons, and written by Hans Binnendijk and George Stewart, the report broke important new ground. Provocatively titled Toward Missile Defenses from the Sea, the study’s authors were prescient in envisioning the role Aegis BMD is playing today. Their report noted, in part:

During the past several years, national intelligence estimates have indicated a growing missile threat from North Korea, Iran, and Iraq that will continue to increase throughout this decade… Developments of the past 18 months have created new possibilities for seabasing of national defenses against intercontinental ballistic missiles… Using missile interceptors based at sea to defend the United States against ICBMs offers several advantages, the most important of which are flexibility and control. The most cost-effective option for a potential seaborne deployment is the use of upgraded Aegis radars and modified SM-3 missiles for boost-phase intercepts onboard existing combat ships stationed near the Korean Peninsula and the eastern Mediterranean. In addition to providing a layer of boost-phase defense, ships at these locations would provide radar coverage early in the flight of an ICBM – a valuable asset to the midcourse defense layer.

The Global Strategic Assessment 2009, mentioned in an earlier post, addressed the need to deal with the threat of weapons of mass destruction as one security threat among a range of others. However, the U.S. National Defense University considered the threat of ballistic missiles carrying WMD so important that it merited a more complete report, and the next year it published a report entitled Ballistic Missile Defense: Past and Future. Unlike the earlier Toward Missile Defenses from the Sea, this report did garner the attention of many, because it painted the threat in stark terms, noting, in part:

As demonstrated by the attacks on New York and Washington on September 11, 2001, there are those in some parts of the world who are not deterred by the threat of invasion or even nuclear retaliation. A national missile defense system could provide a shield from destruction in the event of a threatened or actual launch by a rogue state leader or a powerful transnational terrorist group as well as an unintentional launch by Russia or China… It is for this reason that serious consideration and funding is being provided for a limited ballistic missile defense system that could potentially be effective against such increasingly likely events.

Today, the nation is organized and moving out with alacrity to deal with this compelling threat. The U.S. Missile Defense Agency’s latest program update describes the scope of the threat:

The ballistic missile threat continues to grow in size and complexity. Current trends indicate that adversary ballistic missile systems, with the integration of advanced liquid- or solid-propellant propulsion technologies, are becoming more mobile, survivable, reliable, accurate, and capable of flying longer distances. In 1972 only nine countries possessed ballistic missiles. Today, the number of countries possessing ballistic missiles is over twenty, including hostile regimes with ties to terrorist organizations. Not only are missiles proliferating, but also many of the countries acquiring them are making their own improvements to missiles bought on the global arms market and developing their own capabilities to produce them indigenously. Rockets have already been used by terrorist organizations, and missiles and rockets with better guidance systems, longer range, and more destructive power are proliferating.

Potential adversaries are increasing Short-Range Ballistic Missile (SRBM) and Medium-Range Ballistic Missile (MRBM) inventories and developing Intermediate-Range Ballistic Missile (IRBM) and Intercontinental Ballistic Missile (ICBM) technologies. With the dramatic proliferation of over 1,200 additional short- and medium-range ballistic missiles over the past five years, today there are more than 6,000 ballistic missiles and hundreds of launchers in countries other than the United States, Russia, China, and our NATO Allies. These inventories of thousands of short- and medium-range ballistic missiles constitute 99 percent of the threat and far outnumber the missile defense interceptors we have in the field today.

According to numerous sources, in one year potential adversaries launched more than 100 ballistic missiles in tests and demonstrations, a significant total. This spike in ballistic missile launchings, especially in the short- to intermediate-range category, was particularly pronounced in Iran and North Korea as well as in China. The ballistic missile threat that first emerged over a half-century ago is now a multi-headed hydra compelling a robust United States national response.