What You Need to Know: The U.S. Navy’s nuclear-powered fast attack submarine, USS Seawolf (SSN-21), was recently spotted arriving in Yokosuka, Japan, thanks to sub watchers on social media. This marks the second notable appearance of a Seawolf-class submarine in recent months.

-The Seawolf, one of only three boats in its class, is renowned for its speed and advanced capabilities. Initially designed to replace aging Los Angeles-class subs, the Seawolf program was cut short due to high costs.

-The presence of the Seawolf in the Western Pacific underscores the U.S. Navy's strategic focus on the region, notably in response to China’s influence.

The United States Navy doesn't generally announce the movements of its submarine fleet. However, in the era of social media, it has become just a bit easier to track where the "Silent Service" operates – and on a few weeks ago, sub watchers on X, the social media formerly known as Twitter, reported that the nuclear-powered fast attack submarine USS Seawolf (SSN-21) arrived in the port city of Yokosuka in Japan's Kanagawa Prefecture.

Images of the submarine, the fourth to be named after the solitary fish, showed tug boats aiding it as it arrived in port. According to a report from Newsweek, "The prefectural government has confirmed the visit by the American submarine."

The deployment puts the advanced attack submarine essentially in China's backyard, and the U.S. Navy likely wanted Beijing to know that USS Seawolf was in the neighborhood!

This is also the second time since May that a Seawolf-class submarine became a minor social media star after a photo of USS Jimmy Carter (SSN-23) was captured in May showing that boat arrived in San Diego before quickly heading back to sea.

Sole Seawolf-class Boat in Service

The U.S. Navy operates just three Seawolf-class submarines, and the boats are known for their advanced capabilities, including speeds of 35 knots submerged and a robust armament capacity. The nuclear-powered fast attack boats were developed to replace the aging Los Angeles­class fast attack submarines (SSN), but due to the end of the Cold War and budget constraints, the program was cut short. One factor for the reduction was the cost, with each boat coming in at around $3.5 billion.

In addition, the maintenance of these fast attack submarines has been costly and slow, particularly with USS Connecticut (SSN-22), which has faced extensive repair delays after a 2021 collision with an n uncharted seamount in the Pacific Ocean. That collision caused significant damage to the boat, while 11 sailors were injured. The damage was to the forward section of the nuclear-powered submarine, including its ballast tank, and was significant enough that the sub was forced to make a week-long voyage on the surface from the South China Sea to Guam.

The repairs could cost upwards of $80 million, and it won't be until at least 2026 that USS Connecticut returns to service.

Though SSN-23 didn't suffer a similar mishap that sidelined SSN-22 – or at least the U.S. Navy has never acknowledged one – the former boat has been at Bremerton, Washington for maintenance. It isn't clear when USS Jimmy Carter, named after the 39th U.S. president, will be back in operation.

Nor is it known how long USS Seawolf could be deployed to the Western Pacific, but the U.S. Navy regularly rotates fast attack subs to the region.

Author Experience and Expertise: Peter Suciu

Peter Suciu is a Michigan-based writer. He has contributed to more than four dozen magazines, newspapers, and websites with over 3,200 published pieces over a twenty-year career in journalism. He regularly writes about military hardware, firearms history, cybersecurity, politics, and international affairs. Peter is also a Contributing Writer for Forbes and Clearance Jobs. You can follow him on Twitter: @PeterSuciu. You can email the author: [email protected].

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