The mystery of South Korea’s nuclear-powered submarines

We’re used to applying an instant mental discount to anything US President Donald Trump says, either because he’s uninformed about the subject he’s making confident declarations about, or because whatever he says today could be contradicted by a statement made with equal self-assurance tomorrow.

Yesterday’s statement on Truth Social stating that the US will help South Korea build nuclear-powered submarines is a case in point.

It will be impossible to make complete sense of the statement until we hear more details from both sides, so for the moment, here are some sources which raise various questions and issues:

• The South China Morning Post offers comments from various experts but leads with a statement from South Korean Defence Minister Ahn Kyu-baek that casts doubt on the central Trump claim that the plan is for South Korea to build submarines at an American shipyard. Korean conglomerate Hanwha recently purchased Philly Shipyard in Philadelphia. Asked whether the government’s plan is to build the submarines in South Korea using US nuclear fuel, the minister replies, “That’s correct”. This was the government’s position going into the meeting with Trump.
• Yonhap News Agency reports comments from South Korea’s Foreign Minister Cho Hyun which are vague about building submarines in a US shipyard (“President Trump had suggested he understood our need, saying he has to look into it internally, but the president unexpectedly expressed support”), but the rest of his comments are more about the US providing nuclear fuel to South Korea, which again suggests domestic production. Reuters too puts the emphasis on South Korea’s domestic program. More background on that project here.

• The US currently builds nuclear-powered submarines in only two shipyards: Groton, Connecticut and Newport News, Virginia. This article offers some details about the practical barriers to setting up a third facility, which “would require radiological licensing, the creation of secure perimeters, and training a specialised nuclear-qualified workforce”. All possible, of course, but it would take years.
• Why does South Korea want nuclear-powered submarines? One motivation might be China’s growing fleet, but another comes from photos that emerged from North Korea in March of what might be a new nuclear-powered and nuclear-armed submarine built with Russian help. The most effective way to track and, in wartime, destroy, such a submarine is with a nuclear-powered vessel of one’s own. The diesel-powered boats South Korea currently operates cannot keep up with a nuclear vessel.
• The possible implications of this announcement for the AUKUS arrangement are explored by various Australian analysts in this ABC piece, and they are relatively sanguine. Jennifer Kavanagh from the Defence Priorities think tank, speaking on Australian radio, expressed concern about the ability of the US industrial base to meet American, Australian and now potentially South Korean submarine orders. (Kavanagh also wrote for The Interpreter this week.)

In Seoul last year, I met with various South Korean analysts, think tankers and academics, and came away with a sense that South Korea was suffering AUKUS envy. At the time, I didn’t attribute this primarily to the fact that Australia was getting nuclear-powered submarines and South Korea wasn’t. Sure, there have long been advocates for such vessels in South Korea, but my sense was that AUKUS envy had less to do with hardware than with relationships. As in: “How come the Americans trust you guys with this technology, but not us?”

There’s so much we still don’t know about this agreement, but it appears that South Koreans didn’t need to be so jealous. Japan will surely now be thinking that they too can be trusted, and that they do not want to be left behind.