Constanta, Romania: This past weekend was spent aboard the Romanian Navy’s Danube going cruise ship, engaging in a European-American Security Dialogue. The focus was the Black Sea and its vital geostrategic importance to Russia, NATO and Europe. However, the Black Sea poses a fundamental contradiction for NATO. Only relatively recently has NATO been devoting greater attention to the Black Sea. In the past, the Baltic Sea region was viewed as more important for two main reasons. First, more NATO states are located there or nearby, particularly ones with larger militaries: Britain, Poland, France and Germany. Second, during the Trump administration, the notion of a Russia fait accompli, mainly seizure of the three Baltic States-Estonia, Latvia and Lithuania-gained prominence. In reality, Russia has no intention of risking a war with NATO. The centrepiece of NATO is Article 5 mandating that an attack against one is an attack against all ensuring that war is the least likely of outcomes. The Balts are safe and secure. Perhaps surprisingly, however, only four of thirty NATO member states border directly on Russia: Estonia and Latvia in the Baltic; Norway in the high north; and the United States in Alaskan waters. Hence, given history, geographic proximity produces a certain sensitivity and vulnerability of the Baltic to Russian aggression. But Russia regards the Black Sea as its strategic centre of gravity, not the Baltic. The Black Sea is Russia’s highway to Moscow’s most important national security priorities and lines of interest in the Mediterranean, Africa, the Middle East and Asia. The Black Sea is about the size of Sweden; roughly 740 miles from west to east and 400 miles north to south; bordered by three NATO members- Romania and Bulgaria in the west and Turkey to the south – Russia and Ukraine, including Crimea to the north; and Georgia to the east. Its deepest depth is about 7000 feet. Russia regards the Black Sea as its strategic centre of gravity, not the Baltic. Russia maintains its Black Sea Fleet stationed in Sevastopol in Crimea along with formidable land, air and defence forces that assumed greater significance following Russia’s 2008 occupation of Georgia’s South Ossetia, the 2014 annexation of Crimea and deployment of its forces in the Donbas and eastern Ukraine where conflict persists. In response, NATO has gradually increased its naval and air force presence and freedom of navigation missions in the Black Sea. Given the importance of the Black Sea to Russia, more must be done. The double dilemma is how to convince NATO leaders and the public of the strategic importance of the Black Sea and then take appropriate action. The Black Sea only has one egress chokepoint through the narrow Bosporus and Dardanelles in the west, strictly controlled by the 1936 Montreux Convention and Turkey limiting the size, number and time non-riparian naval ships can enter and stay in the Black Sea. No foreign submarines are permitted. The Black Sea however can become a vital geostrategic asset for NATO if several factors are considered. Land logistics across the Balkans to Romania have not been modernized. The Danube is not deep enough in many places to sustain larger traffic vital to transporting cargo and resupplying military needs. Dredging the Danube to four meters or about twelve feet means all river-borne traffic and trade can be doubled with obvious positive geoeconomic, financial and military implications that could make Constanta, Romania’s largest, port equivalent to Rotterdam in throughput. And the strategic balance can be altered by NATO should Romania field the capability to threaten the Black Sea Fleet in its home waters. The cost-effective means to achieve this objective is with long-range (600 miles) missiles. And the most effective means is through manned or unmanned survivable missile-carrying submarines to challenge the Black Sea Fleet and permissible for Romania to acquire under the Montreux Convention. Merely beginning an examination of this military option will certainly draw attention to the Black Sea and begin moving the strategic balance in NATO’s favour. There is a smart way to do this. The model is RUKUS. “Ruckus” is a huge disturbance in the American language. The UK, US and Australian plan to build nuclear submarines called AUKUS can be put into a Romanian context by considering a building or buying not nuclear but small, diesel-electric missile-carrying submarines. RUKUS will indeed cause a ruckus in certain parts of the world; reinforce the importance of the Black Sea; and give NATO a new and effective deterrent tool. But will this idea ever be raised? Strategic logic says yes. NATO decision-making is not so clear. The writer is a senior advisor at Washington, DC’s Atlantic Council and a published author