^[1]A lively debate has emerged on Australia’s $8 billion acquisition of three Hobart-class Air Warfare Destroyers (AWDs*). Some see the possibility that the new government in Canberra might add another AWD to this procurement order—though ASPI’s Mark Thomson has done an excellent job of setting out the counter arguments ^[2]. Others have criticised AWDs as being both overly expensive and unnecessary in light of advanced anti-ship weaponry, with Hugh White being among the most vocal ^[3].

White even proposed scrapping larger destroyers in favour of smaller vessels armed with anti-ship weapons ^[4]. He doesn’t specify the exact size of these vessels, which makes it difficult to directly argue against. But clearly, he’s talking about vessels with significantly less displacement than the 7000-tonne AWD or the larger frigates that are staple of both the British and Canadian naval fleets. He likely envisions a surface fleet composed of relatively small frigates, such as the 3,000-tonne Anzac ships—without the more formidable capabilities provided by either the AWD or even the remaining Adelaide-class guided missile frigates, which the AWD is designed to replace.

Hugh White’s comments have generated more than their fair share of criticism ^[5], including his flawed use of history and understating the need to safeguard shipping lanes. I want to specifically address his proposal that the Royal Australian Navy (RAN) should opt to procure smaller surface ships, which are too often seen as a panacea to the ills (and costs) of acquiring larger vessels.

To be sure, smaller ships are cheaper to construct and build. Such an advantage shouldn’t be casually dismissed, especially at a time of possible budget tightening. Yet White also argues for a greatly expanded fleet of submarines—by doubling the number of expensive Collins replacements to 24 ^[6], thereby eating up any savings gained from scrapping the AWD and then some. To compensate, the RAN would likely have to settle for a future surface fleet structure that’s scaled back not only in terms of ship displacement but in fleet size as well.

Large warships also have certain benefits compared to their smaller brethren. For one, vessels like the AWD have better sea-keeping characteristics ^[7], due to their size and heavier displacement. This could prove especially useful when facing the sometimes large waves around Australia. Another factor associated with large ships is their greater fuel capacity and interior volume to hold supplies ^[8]. As a result, they also generally enjoy better endurance than smaller vessels and good operational range for their size—a fact that holds true even with possible trade-offs between displacement and fuel consumption.

Large warships also have more space to hold military equipment, including combat systems, weapons, communications, and sensors. For example the Aegis combat system and vertical launch system (VLS) of the Hobart class, which together provides a particularly potent area air defence (AAD) capability. Indeed, Hugh White goes to some length to criticise AAD as an unnecessary, higher-end capability, which he sees as inextricably tied to providing cover for equally unnecessary amphibious operations.

Yet this depiction underplays the versatility of AAD, even as it ignores the full range of capabilities provided by a large warship like the AWD. Yes, these Aegis ships can serve a useful role facilitating amphibious operations. But they also provide a prudent means of defence against air threats for naval surface ships more generally—a capability that provides an additional layer of protection to supplement the relatively limited point defence on RAN’s existing Anzac frigates.

One shouldn’t underestimate the importance of AAD. It provides not only general protection for RAN or allied naval task groups, but is an important pathway to ensure continued interoperability with US Navy. For example, Aegis ships have the potential for remotely engaging targets using other available radar sensors, which could be combined with fifth-generation aircraft to form an integrated sensor network ^[9] amongst allied air and naval fleets. At the very least, these ships provide a crucial means for the RAN to help facilitate the continued integration of its less sophisticated warships into USN carrier strike groups.

Yet these ships also feature a whole suite of other capabilities. The AWD incorporates a sophisticated command-and-control system, so it can not only protect allied naval task group with AAD but also has the capacity to take command of them. The ships will have a formidable anti-ship capability provided by Harpoon missiles and torpedoes and be equally adept at anti-submarine warfare. One should also not forget that these ships are armed with a sizable 48-cell VLS which can potentially hold Tomahawk missiles for land-attack missions and, if the Aegis system gets upgraded, even more advanced Standard Missiles to provide an anti-ballistic missile capability.

The AWD is an inherently versatile platform capable of holding a range of different capabilities, with a capacity for undertaking a variety of missions not easily replicated on smaller vessels. With their larger hulls, the AWD enjoys not only greater flexibility in terms of choice of armaments, but also a stronger capacity to be refitted with new technologies and equipment in the future. Small ships like the Anzac can also be refitted for different missions, recently demonstrated by their air defence upgrade, including a single 8-cell VLS. But the Anzac’s smaller size also definitely limits their architectural flexibility.

It therefore seems only prudent for the RAN to proceed with acquiring a true multi-purpose ship like the Hobart-class AWD, which has versatility in choice of armaments, architectural flexibility when it comes to refits, and continuing high-levels of naval interoperability with Australia’s most important ally. Smaller vessels might be a tempting way to avoid their high costs. But they also entail strategic risk, especially if the higher-end sea control capabilities derided by Hugh White are ever needed.

*Strictly, these ships should be designated DDG for guided missile destroyer, but AWD has become the common usage.

David S. Mc ^[10]Donough  ^[10]is a SSHRC post-doctoral fellow in the Department of Political Science, University of British Colombia and a research fellow in the Centre for Foreign Policy Studies at Dalhousie University. Image courtesy of US Navy ^[11].