Russian warships patrol the surface of the Black Sea, launvhing missiles at Ukrainian cities and towns as part of a near-daily assault. While also enforcing a de-facto blockade, leaving ships in little doubt of he consequences if they try to break it. Such is the importance of this shipping route for both sides. For along time Russian ships moved with relative impunity. And a grain deal that alllowed Ukraine to export from its ports on the Black Sea allowed for an uneasy status quo to hold. But after Moscow withdrew from that deal in the summer and stepped up attacks on Ukraine’s ports, and Kyiv began a counteroffensive to retake land occupied by Russia in sourthern and eastern Ukraine – the Black Sea has become one of the most active fronts in the war. For weeks, Kyiv has been sending a new class of sea drone – essentially unmanned speed boats packed with explosives that can travel many miles – seeking to create havoc and disrupt as much of Moscow’s war machine as it can to help the forces on land. The boats can reach speeds of up to 50mph and can carry a payload of explosives of up to 300 kilograms, according to reports. It is the type of innovative warfare that Kyiv has repeatedly used to push back against a far larger military force. These sea drones have been backed up by missile strikes, including using long-range Storm Shadow missiles from the UK. The most recent scalp? What is believed to be the largest Ukrainian attack on the headquarters of Russia’s Black Sea fleet since the start of Vladimir Putin’s invasion. Kyiv said that the attack on the base in the city of Sevastopol in Russian-occupied Crimea struck a submarine – which analysts suggested was likely a Kilo-class attack submarine that can launch cruise missiles of its own – and a landing vessel. It is thought that this is the first documented successful attack against a Russian submarine during Moscow’s 18-month war. Before that, Ukrainian special forces regained control of a number of oil and gas drilling platforms that Russia has used to help control the Black Sea in a “unique operation”, the country’s military intelligence (GUR) said. The UK’s Ministry of Defence has previously said the platforms could be used to launch helicopters, position long-range missile systems and as a base for forward deployment. ”Russia has been deprived of the ability to fully control the waters of the Black Sea, and this makes Ukraine many steps closer to regaining Crimea,” the GUR said. Meanwhile, two commercial ships have docked at a Ukrainian port in recent days as Kyiv steps up efforts to unilaterally break Russia’s blockade, using a corridor hugging the Black Sea coast of its southern neighbours and Nato members Romania and Bulgaria. Keir Giles, a senior consulting fellow of the Russia and Eurasia Programme at the Chatham House think tank, said the focus on the Black Sea by Ukrainian forces was a “relative change” and they aren’t “abandoning things they are doing on the front line in the east.” He said: “There are more noticeable things happening now that operations against Crimea are picking up pace. But that’s after a long period of preparation. “We saw earlier the attacks by missiles and special forces landing to reduce Russia’s air defence capability in Crimea and now as a result of that they [Ukrainian forces] can carry out those other operations that rely on those air defences being ineffective. “And that’s why we’re seeing this uptick in the pace... It’s also part of the process of eroding Russia’s sustainability of its hold on Crimea... making it so it will eventually be untenable.” As well as the strategic importance of the Black Sea, there is a symbolic element that can prove a powerful tool. Russia’s annexation of Crimea in 2014 is soemthign that Kyiv has been seeking to avenge for a long time. Hence the talk from Ukrainian officials about the retaking of Crimea being a long term goal (as well as the rest of the territory Russia has occupied during its current invasion). For Russia – and Putin in particular – there is also deep sumbolism in Crimea and the Black Sea. “It is a means by which they can throttle Ukraine, throttle its economy. As soon as they seized Crimea in 2014 it immediately compromised Ukraine’s ability to be able to trade and access the Black Sea from all of its eastern ports,” Giles says. “So from Crimea, Russia can project power over enormous distances, its a kind of outpost of Russian military power,” he added. Giles adds: “Ukraine doesn’t need control of the Black Sea to survive, it needs access to the Black Sea to survive. It’s needs the resumption of peaceful shipping without constantly being under threat from Russia. “That unfortunately is not a problem that will go away with the active phase of fighting in Ukraine. That’s one of the reasons why the idea of bringing the actual fighting to an end in a negogiated settlement with Russia is so fraught, because it means Russia can hold the Ukrainian economy hostage, by keeping that strangehold on its ports, particularly if it remains in control of Crimea.” Kyiv has repeatedly said that any peace settlement would need to include the return of all Ukrainian territory. We can expect Ukrainian attacks on the Black Sea and the Russian fleet in the area to continue. It is a way of keeping the pressure on Moscow while ground troops battle for every bloody inch on the fronlines in southern and eastern Ukraine. Any big hits, such as the recent one on the kilo-class submarine provide a propaganda boost as well as harming Russian capacity. Neither Kyiv or Moscow will want to cede anything in the Black Sea, so this will become an increasingly important part of the war. 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