At the end of 2022 – a year of wars, pandemics, weather disasters, and attempts at nuclear coercion – several media outlets published a photograph of a rare event.

It is true that the photograph only interested a small group of viewers: those with an unhealthy fixation on strategic nuclear arsenals.

It showed an American Ohio-class ballistic missile submarine (SSBN), USS Tennessee, on the surface alongside a British Vanguard-class SSBN somewhere in the Atlantic.

ohio class submarines

Ballistic missile submarines (colloquially called “boomers”) from different nations surfacing next to each other are extremely unusual. But the photo, taken on November 22 during joint training, also included a helicopter apparently conducting anti-submarine warfare (ASW) operations and a low-flying E-6B Mercury jet.

It is an image loaded with firepower. The US SSBN has 20 launch tubes, and while the individual warhead load of each Trident missile may vary, the sub likely carries about 90 warheads.

The British SSBN probably carries another 40. And then there are the planes. The E-6B has two missions: to act as a relay channel for communications with US SSBNs and to support the US Strategic Command National Command Authority. In this latest mission, the aircraft embarks on a small combat staff capable of launching ICBMs.

The photo was made public on December 13. There’sThere’s a lot going on in it, so let’s unravel the messages. There are five of them: alliance solidarity, SSBN survivability, ASW superiority, and a resilient line of command authority to deter any attempted beheading attack on Washington or London.

Furthermore, it reminds Russian President Vladimir Putin – and the world in general – of what a classic nuclear deterrent looks like.

The interesting thing is that the SSBN of the triad has been chosen to transmit those messages. In recent history, ballistic missile submarines have been, at least for the Western nuclear powers, the last guardrail of a nuclear deterrent.

Sailing silently and invisibly through the ocean depths, virtually invulnerable to surprise attack, they are the heart of America’s assured second-strike capability.

But in this case, the boomers have moved from the invisible to the visible realm. Furthermore, US SSBNs have behaved unusually elsewhere as well. The USS Rhode Island was called Gibraltar on November 1.

This stopover occurred shortly after the West Virginia stopover at Diego Garcia, from October 26 to 31. Since West Virginia operates out of King’sKing’s Bay, Georgia, calling at Diego Garcia demonstrates the impressive reach of the boomer fleet.

A couple of weeks earlier, the same submarine had surfaced in the Arabian Sea (of all places) to embark on the commander of US Central Command – an implicit message to those thinking about US nuclear commitments.

What makes the recent spate of port calls a little more puzzling is that America’sAmerica’s boomers have gone to great lengths to show that they are not dependent on dockside operations.

It is true that during the visit to Diego García, West Virginia made a crew change. But in May 2022, Alabama demonstrated the ability to swap Blue and Gold crews at sea. And a couple of months later, two SSBNs conducted “vertical refueling” exercises – a fancy name for aerial refueling – while at sea.

Washington seems to be implying that, in a crisis, she does not rely on port visits to stay stationed.
These types of visits by US SSBNs have been relatively rare in recent decades, although in earlier times, they tended to be more common.

The first such visit took place in April 1963, when the USS Sam Houston visited Izmir, Turkey, as part of Washington’sWashington’s attempt to reassure the Turks that they remained covered by the US nuclear umbrella after the withdrawal of the Jupiter missiles. as a tacit prologue to the resolution of the Cuban missile crisis.

As large ballistic missile-carrying submarines became the most surviving leg of the US nuclear triad, the ranges of submarine-launched ballistic missiles improved, and the possibility of some kind of terrorist attack increased against a submarine in a foreign port after the attack on the USS Cole. Again after the terrorist attacks of September 11, 2001, US SSBNs remained at sea, patrolling.

In 2003, ships were specifically instructed not to conduct port visits except to US naval installations. That rule lasted for 12 years until the end of 2015. But even after that, port visits remained rare. Security remains an important consideration.

Of course, there is a second part to this story. To fully appreciate what is happening, readers need to remember the events of 1991.

The Cold War was over. And on September 27, President George HW Bush introduced several presidential nuclear initiatives to reduce the number of nuclear weapons deployed on the front lines and relocate those weapons back to the continental United States.

The initiatives covered both shipborne and land-based warheads, and the effect was to “denuclearize” a large percentage of the US Navy. All surface ships and most submarines – SSBNs were the exception – stopped carrying nuclear weapons.

But the world of 1991 did not last long. In particular, the rise of Asia and the return of strategic competition between great powers began to take their toll.

Allies and partners, seeking clearer signs of US nuclear commitment to their defense, began to show less interest in the non-nuclear navy. This was especially true in the Indo-Pacific, a largely maritime setting.

If the US Navy wasn’twasn’t going to help expand nuclear security in the region, who was going to? The air forces could deploy high-visibility strategic bombers to the region during crises, but the effect could have been more varied.

The recent review of the US nuclear posture shows that Washington is beginning to think more deeply about the future shape of the US extended nuclear deterrent.

In the Indo-Pacific, extended deterrence agreements have traditionally played second fiddle to the European ones. But the review portends more intensive consultations, higher-level engagements, and, where possible, port visits and strategic bomber missions.

These visits are intended to assure allies and partners of Washington’sWashington’s ongoing commitment to “expand” its strategic nuclear deterrence to protect their vital interests.
South Korea looms as a possible starting point because it played host to a steady procession of American SSBNs in decades past.

Japan and Australia are likely to be seen as more sensitive cases: neither is used to seeing a visit by an SSBN as a form of guarantee.

Even so, nuclear deterrence already plays an increasingly important role in the Indo-Pacific, and that role is more likely to increase rather than decrease. Australian policymakers should be alert that the region’s nuclear umbrella is taking on a new and more visible shape.

And you have a special interest in the lifespan of America’sAmerica’s extended deterrence; we are not as well placed as other US allies to pursue what might be euphemistically called “alternative options.”