Weighing a Dedicated Ballistic Missile Defense Class
By Taylor Marvin
I’ve previously discussed what I see as the deficiencies of Mitt Romney’s naval policy: Romney hasn’t made a compelling argument why the fleet should grow to 350 ships beyond vague notions of national strength, and hasn’t explained why he thinks even a marginally larger fleet will be an effective power projection force able to penetrate dangerous anti-access no-go zones. However, in a recent interview with Defense News Romney advisor John Lehman and his conflicts of interest made an interesting suggestion: building two new classes of ships, a frigate and a dedicated missile defense ship. The new frigate proposal is arguably a good one, as the impending retirement of the antiquated Oliver Hazard Perry class and small size and restricted range of the upcoming Littoral Combat Ship make it unsuitable for the routine sea policing and showing the flag missions frigates excel at.
More controversial is the proposal for a dedicated ballistic missile defense (BMD) ship. To reduce development costs, Lehman explains, the ship would be built on either the existing DDG-1000 (guided missile destroyer) or LPD 17 (San Antonio class amphibious transport dock) hull. Calling the proposal a missile defense “ship” rather than destroyer is important, Lehman explained, “because to have the kind of power aperture needed for the new radar, there is always a conflict between a deployable battle group ship and a missile defense ship. The latter is in elevated [readiness condition], tied to a specific area. It can’t deploy with the battle group.”
This is an interesting proposal. Offshore ballistic missile defense is a growing mission for the Navy, and anti-ship ballistic missiles (ASBM) like China’s formidable DF-21D system are a major threat to surface ships. A dedicated anti-ballistic missile (ABM) ship capable of targeting and destroying ballistic missiles would certainly increase the survivability of carrier strike groups, as well as serve in the region BMD role.
However, there are also numerous problems with this proposal, and it merits careful consideration. The greatest asset of the current fleet composition is its versatility. Destroyers contribute to carrier strike groups as well as perform solo sea policing, and are capable of anti-submarine, anti-air, and surface warfare roles. For all the talk about the demise of carriers, their power projection capability will remain reliable and unrivaled in anything but a major war, which is unlikely to occur in the future. As the United States is unable to predict what type of future conflicts it will involve itself in, versatility is paramount to cost effectiveness, especially as the cost of individual platforms grows.
This is a problem for a dedicated ABM ship. Whiled we can’t say much about what the capabilities of such a ship would be until an actual proposal is ironed out, it would certainly be tied to a single mission to a greater extent than other classes. But of course, this lack of versatility is the cost of excelling at a single mission. A dedicated ABM ship would have significant advantages over the Navy’s current ABM strategy, which relies on Aegis-equipped Ticonderoga class cruisers (four of which have been kept in service for their ABM capability after previously being slated for retirement) and Arleigh Burke class destroyers, as well as allies’ like Japan’s Aegis ABM-equipped destroyers. Starting in 2016 the Navy is scheduled to procure Flight III Burke class destroyers, which will mount the larger and more powerful Air and Missile Defense Radar (AMDR) system to better perform the BMD mission. However, fitting these ships with the bulky mechanical equipment required for such a large sensor system means compromising their designs, and Flight III’s cost per unit has already risen to between $3 and $4 billion.
These ABM platforms suffer from various deficiencies due to their multirole design. But despite the limitations of BMD based on the Aegis system, these ships’ versatility is an enormous advantage. As Ronald O’Rourke notes:
“In conventional warfighting operations, Aegis ships could be called upon to perform a variety of non-BMD functions, including anti-air warfare, anti-surface warfare, strike warfare and naval surface fire support, and antisubmarine warfare. Locations that are good for performing BMD operations might not be good for performing non-BMD operations, and vice versa.”
Though important, the actual need for BMD is rare. Building a entire ship class dedicated to a rarely needed mission is problematic.
So the question is: do the advantages of a dedicated ABM class outweigh the limitations imposed on more versatile, multirole Aegis BMD ships? Possibly. A dedicated ABM ship would be able to better mount the AMDR system and would likely involve less design compromises. Additionally, utilizing the existing LPD 17 hull as Lehman suggests would likely free up a large amount of space for the Vertical Launch System (VLS) used to house missiles on modern warships, allowing for a dedicated ABM ship to carry more missiles. Most Burke class destroyers are fitted with 96 individual VLS cells; cruisers hold 122. As VLS cannot be reloaded at sea, during a major conflict ships could be forced to return to port to rearm, decreasing the amount of ships the US could keep in theater. Delegating the ballistic missile defense role to from surface combatants to a dedicated ABM ship would free up these ships’ VLS for other weapons. Depending on the flexibility of the design a dedicated ABM ship could also be loaded with non-ABM weaponry while not performing the BMD role.
Even if a Romney election victory leads to a larger, 350 ship fleet, there still is a zero-sum aspect to budgetary decisions — money that goes to a dedicated ABM class doesn’t go elsewhere. These costs are substantial; a dedicated ABM class would be expensive. For all Lehman’s talk of affordability, adapting an existing hull design for a new mission is not trivial, and the rising cost of the Flight III Burke class — in itself a simpler conversion than adapting a DDG 1000 or LDP 17 hull to the ABM role — are not a good omen. Lehman’s remark that the optimum power plant for a LDP 17-derived ABM ship “is not the one that’s in it” is also worrying, from an affordability standpoint. This affordability problem is confounded by a dedicated ABM class’ lack of flexibility, as there’s only so much the Navy can spend on a single mission. While the old arsenal ship idea calls for a large ship able to carry a large number of individual VLS cells is superficially similar to a dedicated ABM ship, the extensive sensors required for an ABM ship would negate the benefits of this “moderate cost, high benefit” proposal.
Worse, it’s not clear what benefit this class would provide. While ASBM are the by far the most dangerous threat facing surface ships, but they are not alone. US and allied forces in anti-access/area-denial environments face many threats beyond ballistic missiles, including cruise missiles, enemy aircraft, and for naval forces, submarines and mines; building a dedicated ABM ship is investing in an expensive class that cannot contribute to combating these threats. More troubling, as opponents of ballistic missile defense have noted for decades, ballistic missile defense is hard. BMD systems has performed poorly in combat — though admittedly modern systems have not had the dubious opportunity to prove their worth in wartime — and when successful in tests do so under carefully controlled conditions. If China really did want to sink a US supercarrier, they throw every anti-access weapons system they have against it: an attack by multiple ASBM warheads using decoys and jamming to degrade US countermeasures, combined with simultaneous cruise missile launches to overwhelm and distract defenders. This gets at the core problem with BMD: it will always be easier for an attacker to simply launch more missiles than the system can deal with. ASBM systems are difficult to build — it is not clear when China’s DF-21D will be an operational system — but are not particularly expensive by unit cost, and will certainly become both more common and proliferated in the future. It’s not clear if investing limited resources in a dedicated ship class is a good idea if an ABM ship would not actually be able to perform it’s mission, especially since fleet ballistic missile defense is not the “limited, unsophisticated strike” modern BMD advocates typically argue their systems are capable of defeating.
Of course if successful a dedicated ABM class would have real benefits. Notably, the ability to reliably to defeat intermediate range ballistic missiles in their terminal phase would allow the Navy to defend itself in a Western Pacific war without targeting missile launch sites in China. This is a core problem with the AirSea Battle concept: hitting missile launchers in China carries a dramatic potential to escalate a previously maritime conflict. Just as the British refrained from striking the Argentine mainland during the Falklands conflict, so should the US avoid potentially escalatory mainland strikes in a future war. Effective and reliable navla ABM ability could allow this. But this is a huge if, and it is very unclear if this uncertainty justifies an expensive new ship class.