Ukraine’s successes against Russia’s have markedly changed the dynamic of naval warfare in the Black Sea. In April 2022, using uncrewed systems and surveillance drones, Ukraine struck and sank Russia’s Black Sea Fleet flagship, the Moskva. By October of the following year, Kyiv pushed Russia’s navy from Sevastopol on the Crimean Peninsula and managed to reopen contested sea lanes for the export of grain – a vital outflow for its economic sustainability. That Ukraine does not even have a navy makes these victories even more impressive.

Ukraine’s successful use of emerging technology is worth drawing lessons from, but it is important to limit suggestions that this represents a sea-change in the character of war and a challenge to the primacy of navies. Are these new capabilities forcing modern navies to change their behaviour? Certainly. Does it mean that large vessels are no longer relevant in the era of the naval drone? No.

The artificial limits on operations in the Black Sea and the broader value of navies need consideration when looking to apply lessons from beyond the Ukrainian theatre. Naval officers and politicians alike should be wary of drawing too sharp conclusions from Ukraine’s use of autonomous unmanned underwater vehicles and land-based long-range precision weapons. Looked at in isolation, the developments in the Black Sea offer as many of the wrong lessons, as the right ones.

The Black Sea is uniquely constrained by the politics of the Bosporus Strait. Turkey – which manages the Bosporus Strait under the 1936 Montreux Convention – has designated Russia’s invasion as a ‘time of war’, an obvious but critical distinction that prevents either warring party from transiting naval vessels into the Black Sea. Russian naval vessels based on the Crimean Peninsula can, however, return to port. For the foreseeable future, the Black Sea is a restricted area for naval operations.

As Ukrainian successes continue, Russian naval power in the Black Sea is degrading, without the possibility of reinforcement or augmentation. There are, however, few other locations on the high seas that are subject to such constraints. While maritime chokepoints exist in other theatres – the Malacca Strait, between Malaysia and Indonesia, for example – none are as definitive as the Bosporus Strait and Turkey’s governance of the freedom of navigation into the Black Sea. Much of the conversation about lessons from Ukraine’s Black Sea successes omit this crucial detail.

Ukraine’s performance also needs contextualisation. Most of Kyiv’s attacks have been against vessels at anchor and in port with notable high-profile exceptions such as the sinking of the Moskva. At the same time, Kyiv’s successes are as much about Russian failures as Ukrainian successes. The Black Sea Fleet has, thus far, not been given an achievable mission by Moscow but its long-range fire capabilities do enable it to strike Ukrainian targets.

Ignoring the unique context of the Black Sea and Russian operational failures could lead Ukraine’s Western allies to draw the wrong conclusions about the future of their own naval forces. It is easy to see Ukraine’s successes in not only sinking Russia’s Black Sea Fleet but also forcing a fundamental change in its operations and draw the conclusion that naval drones render large vessels irrelevant. It is not a stretch to suggest that capital ships are simply too vulnerable to such activity and therefore must be shrewdly husbanded to avoid unnecessary risks.

Would Washington or London risk losing a £1 billion Type 45 Destroyer to a $250,000 uncrewed naval drone? If not, some would argue, the West would do well to de-prioritise expensive shipbuilding and redirect its efforts towards more numerous, markedly cheaper distributed drone capabilities.

Technology is, however, fundamentally a tool and not an end. If the inverse was the case, the advent of torpedoes and sea mines should have rendered fleets long obsolete. Allowing the technological tail to wag the dog as opposed to understanding how it shapes questions of war and diplomacy is a sure pathway to obsolesce and defeat.

The introduction of drones, persistent intelligence, surveillance and reconnaissance (ISR), and long-range precision strikes, is changing behaviours and tactics, but does not render fleets any less relevant. Ukraine’s success in the Black Sea has certainly forced a change in behaviour. Russia’s adaptation has been relatively slow in naval terms, at least when compared with that of its army counterparts. It is, however, developing counter drone tactics – for every innovation, there is eventually a counter.

In practice, Russia has mainly relocated operations away from Crimea ceding the nautical field to Ukraine, rather than adjust its operational focus. This could change relatively quickly if Moscow devolved greater command authority to its naval commanders or gave it a viable mission. If Moscow were to change the Black Sea Fleet’s primary task, for example, to interdicting grain exports and targeting shipping, the Russian navy could become far more relevant in the Black Sea.

If political leaders look at developments in the Black Sea and see only cheap assets achieving notable successes against expensive vessels or applying pressure to the global economy, they will miss the broader material value of naval forces and naval power. Naval forces shape conditions for strategic success (including on land), military victory, and political resolution in wartime, and deter conflict in peacetime. Conceptually, this has not changed since the era of Nelson and would be as familiar to the British naval historian Sir Julian Corbett or the American naval strategist Alfred Thayer Mahan as to contemporary thinkers.

This is well recognised by the West’s main strategic adversaries. Moscow retains considerable naval capabilities beyond the Black Sea, including a robust and professional submarine force. Its ability to maintain deterrence and naval diplomacy remain undiminished, as does its ability to conduct land-based targeting. It also possesses a sweeping strategy for its naval and maritime interests and is preparing accordingly. Furthermore, in the Indo-Pacific, China’s People’s Liberation Army Navy (PLAN) is now the largest in the world. While untested in modern combat operations, Beijing has demonstrated a willingness to use hybrid and irregular naval and maritime tactics to assert what it claims are its territorial interests.

Both avoiding drawing the wrong lessons and learning the right ones are inextricably linked to the political nature of naval and maritime operations, and, indeed, the very nature of war itself. Spending billions on vulnerable fleets, politicians may argue, is inefficient when war can be waged via drones for a fraction of the cost, but this is to not properly see the value and utility of naval power.

The test that Russia and China present, as well as emerging challenges – such as the Houthi attacks in the Red Sea – require large fleets of sizeable vessels; naval diplomacy – port visits, joint exercises, and freedom of navigation patrols – require ships of the line; projecting power and operational precision requires presence that only naval forces can bring to bear in a lasting and sustainable manner. Shrinking fleets out of fears of the threat of drones will ultimately see naval forces spread far too thin, a sure path towards strategic irrelevance.