Ukraine’s Victory at Sea

When Russia invaded Ukraine in 2022, Kyiv’s maritime prospects looked bleak. Ukraine had inherited a small number of ships when the Soviet Union broke apart, but Russia destroyed or confiscated most of these when it occupied Crimea in 2014. Then, in 2018, Russia seized three of Ukraine’s remaining vessels and prevented its civilian ships from entering the Kerch Strait, the waterway separating the Crimean Peninsula from mainland Russia. Russia quickly reopened the strait and eventually returned the ships, but the moves laid bare Ukraine’s naval impotence. By the time of the next invasion, the Ukrainian navy’s flagship—an aging frigate—led a meager force consisting of one small warship, several small missile boats, and a handful of helicopters. Two weeks after the war began, Ukrainian commanders were compelled to scuttle the flagship, lest it fall into Moscow’s hands. Russia sank many of the smaller vessels. 

Over the next year and a half, however, Ukraine turned the naval war around. Using drones, cruise missiles, and a variety of unconventional techniques, Ukraine had, by October 2023, driven the Russian fleet from its main base in Crimea to the eastern corner of the Black Sea. The country’s navy succeeded in sinking nine major Russian ships and even reoccupying some lost territory. These victories have been a bright spot for a country that is under continual air attack and stuck in a costly stalemate on the ground. 

Kyiv’s maritime accomplishments will not win the war, but those victories will help the country succeed more broadly. Winning at sea has allowed Kyiv to take troops that were stationed along the coast and send them to the front. It has secured shipping lanes that are crucial to exporting grain and complicated Russian efforts to supply and reinforce Crimea. Over time, Ukraine can build on this success, increasing its leverage in future peace negotiations. For this strategy to succeed, however, Kyiv will require an uninterrupted flow of military aid from the West.

THE RUSSIAN TIDE FLOWS—AND EBBS

When the invasion began, the Russian Black Sea Fleet was far mightier than its Ukrainian equivalent, consisting of the battle cruiser Moskva, five frigates, six modern submarines, 13 tank landing ships, and many smaller vessels suitable for coastal defense. Fighter jets, patrol aircraft, and helicopters supported the fleet. With this overwhelming force, the Russian navy encroached on the Ukrainian coast, launching missiles at Ukrainian cities, and landing forces at the port of Mariupol. To prevent a landing near Odessa, Ukraine had to station an infantry brigade and a powerful armored brigade along the coast—taking 5,000 trained troops and 100 tanks out of play as fighting raged around the country’s two largest cities, Kharkiv and Kyiv. 

But Russia’s early success did not last. A month into the war, Ukrainian missiles fired from drones sank several Russian patrol boats. In the most spectacular episode of the Ukrainian comeback, two antiship missiles launched from the Ukrainian coast struck the Moskva in April 2022. The Russian navy tried to tow the damaged ship to its base in Crimea, but the vessel sank en route. It was the largest warship sunk in battle since the British torpedoed the Argentine cruiser Belgrano in 1982 during the Falklands War.

Two months later, after the Moskva’s demise, the Ukrainian military pushed Russian forces off Snake Island, which is located along shipping lanes near Ukraine’s southern coast. The island became famous in the early days of the war after its Ukrainian defenders sent an expletive-laden message of defiance as Russia took the island. But after repeated Ukrainian missile attacks on resupply vessels, the Russian troops stationed on the island were forced to withdraw in June 2022. 

According to calculations from the Center for Strategic and International Studies, Russia has lost about 40 percent of its naval tonnage in the Black Sea since February 2022. In addition to the Moskva, Ukrainian missiles and drones have destroyed or severely damaged two frigates, five tank landing ships, and a submarine. Strikes on Russian naval headquarters, shipyards, airfields, and air defense facilities in Crimea have weakened the fleet’s shore-based defenses, command-and-control networks, and logistical support. To protect its remaining ships, Russia moved most of them to its naval base at Novorossiysk, in the eastern part of the Black Sea. But even there, far away from the action, the ships were not safe. In August 2023, a Ukrainian sea drone crossed the Black Sea and damaged a Russian warship in the harbor.

Russia’s early triumphs at sea did not last.

Many of the weapons Ukraine has been using against the Russian fleet, although not new, had not been tested in a prolonged naval campaign. Ukraine has shown they can be remarkably effective. Two types of missiles have proved particularly useful. The first is the long-range antiship missile. Ukraine produces some of these missiles domestically and receives some from the United States. They have a range of 100 to 200 miles, enough to keep Russian ships far offshore, lest they suffer the same fate as the Moskva. Although the missiles were originally designed to be placed on ships, Ukraine’s military has adapted them for land-based launchers to reduce their vulnerability to counterstrikes. The second missile variety—the long-range, land-attack missile—complements Ukraine’s antiship capabilities. Produced largely by the United States, the United Kingdom, France, and Ukraine itself, these weapons are fired at static locations and were designed for ground operations, not for striking highly mobile naval targets. By aiming at stationary ships in harbor, however, the Ukrainians have used these land-attack missiles to take out five of the nine major vessels that Russia has lost during the war.

Ukraine’s use of sea drones is an especially novel development in naval warfare. Operated remotely and difficult to spot, these weapons can reach deep into an adversary’s maritime domain while carrying large payloads. And because operators follow the vessels’ movements via video link, they can adjust course, evade countermeasures, and even switch targets if the initial target is unavailable. According to the Ukrainian defense ministry, one such sea drone managed to sink a Russian ship stationed near Crimea in January 2024.

Accurate targeting information has been key to the success of the weapons systems Ukraine uses at sea. GPS-guided munitions must be programmed to hit the correct location at the correct time; hitting the dock after the ship leaves is a waste of a missile that Kyiv cannot afford. Even munitions that can adjust course midflight must be launched with enough accuracy for the missile’s guidance system to find the target. The farther away that target is, the harder the task becomes. The advanced satellite, electronic surveillance, and other intelligence capabilities that the United States and other partners provide are critical.

NO SUBSTITUTE FOR VICTORY

Ukraine has won the battle for the Black Sea. Yet it will be some time before the full implications of this victory become clear, for the current war and for modern naval combat more broadly. The Ukrainian military’s routing of a vastly stronger navy could indicate that conventional surface ships have become obsolete, or it could merely serve as a warning to future naval combatants that without sound tactics and appropriate defensive systems, they, like Russia, will be vulnerable to attack.

Ukraine’s naval success does not spell an end to a war fought primarily on the ground. It does, however, give Kyiv several important advantages. One is political and psychological. Defeating the Russian fleet at sea boosts morale among Ukrainian civilians and military forces. And as Ukrainian President Volodymyr Zelensky makes the case for continued outside support for his country’s war effort, he can highlight this success. Ukraine’s backers, discouraged by the stalemate on the ground and relentless Russian attacks from the air, can point to the naval victory as evidence that military success is possible. 

With Russian ships driven far from Ukrainian shores, the threat of an amphibious attack is gone. Ukraine has therefore been able to redistribute the ground forces that had been guarding the shoreline and leave coastal defense to local militias. Ukrainian ports and coastal settlements are safer, too, easing the anxiety felt earlier in the war when gunfire and missile attacks from offshore Russian warships were a feature of everyday life.

Ukraine’s naval success has been a bright spot amid the costly stalemate on the ground.

Another benefit is the logistical challenge Russia now faces. Moscow is having an increasingly difficult time sending supplies to Crimea as Ukrainian missile attacks threaten Russian transport vessels and periodically shut down the Kerch Strait Bridge, which connects the peninsula to mainland Russia. Although Russia can still send barges across the strait, this workaround strains an already troubled logistics system. Moreover, supply chain interruptions bring suffering to the Crimean population. The peninsula’s increasing vulnerability may persuade Moscow to settle more quickly when peace negotiations finally begin. Otherwise, a weakened Russian military may be unable to fend off Ukrainian incursions, and a suffering population on the peninsula may choose reunification with Ukraine rather than continued hardship under Russian rule.

Finally, Ukraine has reduced—but not yet eliminated—Russia’s ability to interfere with grain exports from Odessa. Pushing back the Russian navy has allowed coastal traffic to move again. Although Russia backed out of a 2022 agreement allowing Ukrainian cargo ships carrying critical shipments of grain through the Black Sea, it has not tried to stop shipments from leaving Ukrainian ports. Moscow could still change its mind. But with its navy forced out of the area, it has only two remaining methods for blocking Ukrainian shipments: laying mines and using its submarines to attack cargo ships. Ukraine’s control of the sea makes these alternatives more difficult. Russia would need to have ships or aircraft to lay mines, and both would be vulnerable to Ukrainian countermeasures as they approach the Ukrainian coast. Submarine attacks on cargo ships, meanwhile, would invite global condemnation, including among developing countries that rely on imported grain and whose support Russia seeks.

Ukraine needs help from its allies to sustain these advantages. Although Kyiv’s supply of antiship missiles is likely sufficient for now, given their relatively infrequent use, the Ukrainian military will certainly need more land-attack missiles from France, the United Kingdom, and the United States. Ukraine will also continue to rely on intelligence support from the United Kingdom, the United States, and other partners to identify targets and Russian vulnerabilities.

GETTING CREATIVE

To build on its success, Ukraine will need to do more than reinforce its current capabilities. Most urgently, the country needs better equipment and training to clear sea mines. Russian mines still constrain Ukrainian operations by confining ships to a few easily interdicted channels. Western powers can provide small boats and equipment to find and eliminate mines at all depths. If Ukraine can neutralize Russia’s ability to block grain shipments through the Black Sea and can keep shipping lanes open, Moscow will lose a powerful source of leverage in any future peace negotiations.

The Ukrainian military must also learn to conduct antisubmarine warfare. Russia’s submarines in the Black Sea are essentially invulnerable; they can fearlessly strike any target at will. So far, Moscow has not used its submarines because of a lack of military targets, as there is nothing left in the Ukraine’s navy worth attacking, and it is reluctant to risk sinking other countries’ cargo ships. But submarines remain Russia’s trump card in naval combat; Moscow need only choose to play it. Ukraine, then, needs to figure out how to neutralize this threat. 

Kyiv will have to get creative. It can’t waste time and money trying to replicate the multibillion-dollar systems of sophisticated surface vessels, submarines, and aircraft that Western navies use to hunt enemy submarines. Ukraine’s fight does not echo the vast scale and existential stakes of submarine battles in the North Atlantic during World War II or NATO’s massive efforts to counter hundreds of Soviet submarines during the Cold War. Kyiv just needs to exert enough pressure to make the five Russian submarines operating in the Black Sea pull back—something it could accomplish with U.S. and NATO antisubmarine weapons and detection equipment adapted to operate on readily available small vessels. That would reduce threats to Ukrainian shipping and ease economic pressure on the Ukrainian government to make concessions in any eventual peace negotiations.

Ukraine needs help from its allies to sustain these advantages at sea.

Finally, Ukraine should build a modest amphibious capability that can threaten Russian positions in Crimea and the Russian rear areas along the Black Sea coast. Small craft, which are available immediately from the United States and other NATO partners, would be sufficient to keep Russian forces looking over their shoulders. Moreover, such small craft can be transported quickly overland, avoiding Russian submarines, as well as the complication of the Montreux Convention, a 1936 diplomatic agreement that allows Turkey to prevent the passage of warships through the straits that lead to the Black Sea. With an amphibious force poised near Russian-controlled territory, Ukraine could draw Russian troops away from the frontlines to defend the coast—the same tactic Russia used against Ukraine at the beginning of the war. Eventually, Ukraine might also use this amphibious capability as part of a campaign to retake Crimea. 

Such an offensive is not possible today. Crimea is strongly defended, and an amphibious assault on it would be extremely complex. Instead, periodic raids into Crimea, such as those Ukraine has conducted in the nearby Kherson region, would make the amphibious threat credible and distract the Russians from the key ground battles inland.

Ukraine’s naval success is dramatic and unprecedented, but the tide of victory could ebb if the United States and other Ukrainian partners cut their assistance. If Ukraine cannot replace the munitions it fires and the equipment it loses in battle, Russian forces will again encroach on Ukrainian coasts and reestablish secure supply lines through Crimea. Were that to happen, Ukraine’s victory at sea could be fleeting.