For much of history, the Royal Navy was the best-manned and best-equipped navy in the world. It has been many decades since that era, and while the Royal Navy (RN) is still potent, it is no longer the supreme force that it once was. Of course, this can be largely attributed to the dissolution of the British empire and the subsequent decline of British economic power. After World War II, the US Navy supplanted the RN as the primary navy of the democratic world, easing much of the RN’s patrol burden and allowing for this decline.

However, the decline of the RN can also be attributed to the tendency of Conservative and Labor governments to make military budget cuts; Britain’s military spending as a percentage of GDP, while high relative to other European nations, is still far below that of the US or Russia. After the Cold War, British defense spending took a nosedive and landed at around 2.3%. In 2015, the UK’s defense spending fell below 2% for the first time in modern history. Of course, these cuts allow for increases in spending on social programs such as the National Health Service, which is why they have been relatively popular. Nevertheless, it is reasonable to interpret reductions to the RN’s budget as a signal that the British government and public alike no longer view defense in the same light that nations such as Russia and the United States do.

The RN’s surface force has been hit particularly hard by austerity, with a marked decline in equipment quantity — for example, its 12 retiring Type 42 destroyers will be replaced by only six new Type 45 destroyers. Similarly, thirteen Type 23 frigates will retire in the near future, to be replaced by only eight Type 26 Global Combat Ships.

It certainly appears that the RN is taking the quality over quantity approach to procurement; while its future force will be relatively small, all the assets are modern and highly capable. The aforementioned Type 45 destroyers, for example, are recognized by experts as some of the best air defense ships currently afloat, the Type 26 is similarly equipped, and the two 70,000-ton Queen Elizabeth-class carriers slated to enter service will be some of the world’s largest and most complex carriers upon commissioning.

Unfortunately for RN proponents, these surface ships are soon to lose a critical capability. As widely reported, the Royal Navy plans to retire its RGM-84 Harpoon anti-ship cruise missiles (ASCMs) by the end of 2018. The Harpoon is a fairly dated weapon, so its retirement alone is not particularly notable. The critical detail is that no replacement for the Harpoon is currently funded, meaning that the Royal Navy is forfeiting its heavyweight surface-to-surface capability for the foreseeable future.

Many sources inside and outside of the RN have expressed their disagreement with the Harpoon’s retirement. However, the RN’s decision to forfeit their heavyweight ASCM capability was made based on careful deliberation, and deeper examination reveals that this decision is not as reckless as some have asserted.

The Harpoon is a subsonic anti-ship cruise missile used to sink or disable surface ships. It has a range of about 80 miles and a 500lb warhead. The Harpoon, in service since the late 70s, is dated and ineffective compared to other modern ASCMs. One of its most significant shortcomings is the 80-mile range, which is significantly inferior to other modern ASCMs. The Harpoon’s retirement is not “premature” per se, since the weapon is rather outdated, and many other Harpoon-operating navies are looking to retire the missile.

Rather, the decision not to procure a replacement means the RN’s Type 45 and Type 26 frigates will not have the ability to directly engage enemy ships from long range. Both classes have relatively large naval guns (4.5” and 5”, respectively), but the ranges of these guns are limited to about 17 miles. In comparison, advanced Chinese, Russian, and American anti-ship missiles can fly  hundreds of miles. Further, naval cannons are relatively weak and inaccurate, while anti-ship missiles have precision guidance and explosive warheads weighing hundreds if not thousands of pounds. Engaging an ASCM-equipped enemy with cannons is not a winning proposition, so the Harpoon’s sans-replacement retirement indicates that the RN has basically decided to forfeit its ship-vs-ship combat capabilities for the time being.

This gap will be temporarily exacerbated by the retirement of the RN’s Sea Skua helicopter-based ASCMs in 2017, leaving the RN completely devoid of any anti-ship missile capability for two years until the fielding of the Sea Venom ASCM in 2020. While the Sea Venom will help mitigate the lack of a heavyweight ASCM, it cannot supplant the Harpoon. The Sea Venom is helicopter-launched, so its range and warhead are vastly inferior to a ship-launched ASCM. Further, helicopters are vulnerable to anti-air missile and fighter attacks.

At a time when other navies are investing in ASCMs and building increasingly complex surface warships, the RN’s divestment may seem out of place. However, there is sound reasoning behind it. First of all, the RN’s warships are primarily built as air defense escorts, not ship-killers. Even if the RN’s ships retained their Harpoon missiles, submarines would still be the preferred asset for eliminating enemy ships. The RN plans to field seven Astute-class nuclear attack submarines (SSNs), which will provide the bulk of its anti-shipping capabilities. Note that the Royal Navy is replacing all seven of its Trafalgar-class SSNs, a testament to the importance of attack submarines in modern naval warfare.

When one considers how the RN will be organized in the future, the decision to retire the Harpoon without a replacement seems less impactful. With two massive aircraft carriers slated to enter service, it is clear that the Royal Navy of the future will be based on carrier strike groups. Since at any given time one of the carriers and a few of the subs, destroyers, and frigates will be undergoing refits, training, or maintenance, it seems that the RN will have one carrier strike group ready at any given time. Each strike group will deploy with a few destroyers, a few frigates, and a complement of attack submarines. In this configuration, each ship has a role: the aircraft carrier allows for strikes against other ships, land targets, and submarines at long range; the destroyers and frigates defend the aircraft carrier from missile, aircraft, and submarine attack; the submarines hunt attack and sink enemy ships and submarines. As part of a strike group, the surface combatants (destroyers and frigates) are employed primarily as defense for the aircraft carrier, not an offensive instrument for attacking enemy ships. Thus, the lack of an ASCM is not of critical importance. If the surface combatants were to operate without a carrier or a submarine, there would be more risk, but the small size of the future RN means that most of the ships will probably be tied up in operations with the carrier group, and carrier-less patrols could still be accompanied with a submarine if necessary.

It is also worth noting that the RN does not face much of a surface ship threat at the moment. The largest naval competitions are taking place in the Pacific, which falls primarily under Korean, Japanese, and US responsibility. While the RN does do occasional freedom-of-navigation patrols and overflights in the South China Sea, its major task is patrolling the Northern Atlantic and intercepting Russian vessels, the vast majority of which are submarines and not surface warships.

One important question is what, if anything, the RN will do to address this deficiency going forward. While the Harpoon’s retirement is certainly not cataclysmic, it could become a significant issue going forwards, especially as the Russian and Chinese navies field increasing numbers of well-equipped surface combatants. Improved anti-submarine tactics among adversaries could also push the RN to take another look at procuring a Harpoon replacement.

There are a number of missiles which could serve this purpose, either on board the Type 45 and 26 or with the F-35Bs of the Elizabeth-class carriers’ air wings. As of now, the RN does not operate heavyweight air-launched ASCMs nor does it have any plans to do so. However, this decision could be easily reversed, as a number of ASCMs are being developed for the F-35, and these could be easily integrated onto the UK’s aircraft in the future. One candidate would be the US’s Long-Range Anti-Surface Missile (LRASM), which the UK has reportedly expressed interest in. The LRASM has been developed from the ground up for use with the F-35, and is a relatively low-risk option with excellent range. The Type 45 and 26 could not launch the LRASM from their Sylver VLS systems, so relatively extensive modifications would be needed. The same issue would be encountered with any other ASCM refit unless the missile could be made to launch from the existing quadruple Harpoon box launchers.

At the moment, it seems that the UK will opt for the LRASM, probably with the F-35B as the sole launch platform. This would leave the UK’s surface combatants reliant on carrier air wings and subs for anti-shipping. But, since all the UK’s options remain open, the eventual decision will likely depend on the military situation going forward; if a surface threat is not perceived, RN brass will have less of an incentive to purchase heavyweight ASCMs. Similarly, political sentiments could also have a bearing on whether or not a Harpoon replacement is pursued, as further military cuts may preclude an ASCM buy. In any case, the UK’s surface warships have lost their long-range anti-shipping capabilities for the time being. While the decision has been finalized, the debate surrounding has not; expect to see naval experts and enthusiasts arguing about over the Harpoon’s sans-replacement retirement for years to come.