In an era marked by hypersonic missiles, cyberattacks, and swarms of drones, nuclear submarines seem to have become one of the few weapons from the Cold War era that, far from losing prominence in the 21st century, have actually gained it.
As tensions rise in the Pacific, Indian, and Arctic oceans, the role of these silent, mobile, and nearly untraceable giants has grown, despite their astronomical costs. Building a nuclear submarine capable of carrying cruise missiles costs between 2,000 and 4,000 million euros. One capable of launching intercontinental missiles can reach up to 9,000 million, which is the cost of the new Columbia class submarines in the United States. When maintenance costs over three or four decades of service life are added, the figure almost doubles.
One of the reasons for the increasing use of nuclear submarines is that they are no longer just platforms for nuclear deterrence, which made them the ultimate weapon for the United States and the USSR for decades. Today, these vessels have multiple functions, from attacking land targets to cutting underwater cables. During the Cold War, the weight of nuclear strategy rested on these monsters that can measure nearly 200 meters and displace over 30,000 tons. Today, submarines are becoming more versatile. And nuclear submarines, with unlimited autonomy, can stay underwater as long as the crew's food lasts.
An example of this diversity of tasks is the American Jimmy Carter, specialized in secret missions, which may include sensor placement, launching and recovering underwater drones, and infiltrating soldiers into hostile territory. The Russian Belgorod seems to do the same. But the adaptability of these weapons is enormous. The United States has converted four of its 18 giant Ohio-class submarines, originally designed to play a starring role in a nuclear apocalypse, by removing their 20 intercontinental missiles and equipping them with 154 cruise missiles. One of these four - they have not disclosed which one - bombed Iran's nuclear facilities on June 22. It is the second time in history - after an attack with over 90 cruise missiles launched against Libya in June 2021 by another submarine of that class, the Florida - that one of these four submarines built to launch intercontinental missiles has been used in combat.
Last Friday, American submarines returned to the spotlight when Donald Trump announced with great fanfare that two of them would be sent to "appropriate regions" due to the "provocative statements" made by former Russian President Dimitri Medvedev. The statements were pure posturing because if anything defines submarines, it is the strategic ambiguity they provide, meaning their ability to be where they are least expected.
However, nuclear submarines have become one of the geopolitical stars of the summer - if that term is acceptable - albeit in the most discreet manner possible.
This is due to two reasons. Firstly, they are marking what may be the first concrete action of two of the closest allies of the United States, the UK and Australia, to create a nuclear defense system independent of Washington. Secondly, partly linked to the former, is that the massive importance of these vessels has starkly exposed the deficiencies in the industrial capacity of the West to manufacture weapons, just as defense needs are growing.
Both crises were starkly evident in the days leading up to Trump's announcement. On July 25, the Defense Ministers of the United Kingdom, John Healey, and Australia, Richard Marles, signed a treaty in Marles' hometown of Geelong for the development, construction, and maintenance of a fleet of 12 nuclear submarines over 50 years.
The Geelong Treaty, as it is informally known, is an attempt by London and Canberra to hedge against the unilateralism of Donald Trump's second presidency. Four days after the signing, U.S. Defense Secretary, Pete Hegseth, announced that the Department would review its participation in the Aukus military agreement with the UK and Australia, signed in 2022, under which Australia would buy between three and five second-hand Virginia-class atomic submarines from the United States in the next decade before jointly developing their own with Great Britain.
Some see the possibility of Washington withdrawing from Aukus, apart from being a very serious warning to other alliances, as a decision promoted almost single-handedly by Elbridge Colby, a senior Pentagon official known for his extreme unilateralism even by the standards of the Trump administration.
However, the fact that Hegseth, who seems to have Trump's trust, supports it gives it a new dimension. Especially because the argument is impeccable: the two shipyards where the United States builds its submarines are unable to accelerate the construction of these vessels for their own Navy. As explained two days later by the Chief of Naval Operations of the United States, Admiral Daryl Claude (known to his subordinates as The Badger, an animal symbolizing tenacity and ferocity in the United States), the world's leading power must increase its production capacity of Virginia-class nuclear submarines, currently at two per year. Otherwise, Claude explained, there will be no surplus submarines for Australia.
For Australia, it is a moral and strategic blow with a touch of mockery, as Hegseth made the announcement just when the Canberra government led by Labor's Anthony Albanese had just made the second payment of $450 to the United States, a sum that will go entirely (like the rest of the $2.6 billion committed) to expanding the shipyards in Lis where the Virginias are made. Of course, there is also the possibility that the Trump administration wants Australia to pay more.
The decision of the Australian and British governments to go it alone is, therefore, a way to keep Aukus afloat, even if the Virginias do not arrive. But it is also a huge challenge for both countries. The Geelong Treaty plans to build 16 new attack nuclear submarines, meaning guided missile-equipped - presumably cruise missiles - but not armed with atomic bombs. It states that these vessels would be for London and Curro for Canberra.
The issue is that, to achieve this, the UK will have to expand its shipyards and also its bases, as it currently only has seven such ships. For Australia, building its four nuclear submarines would be an even greater challenge. But it seems that there is no price high enough to deter more and more governments from the strategic imperative of having nuclear submarines in their fleets.