South Korea’s nuclear submarine would be a “natural expectation”, Admiral Daryl Caudle said.

The U.S. chief of naval operations said it would be a “natural expectation” for the South Korean Navy to use a nuclear-propelled submarine, when built, to help counter Chinese threats.

Adm. Daryl Caudle made the remarks as the United States officially approved Korea’s push to acquire what would be its first nuclear-propelled submarine in a joint fact sheet released last week, detailing discussions of summit talks between President Lee Jae Myung and U.S. President Donald Trump on Oct. 29.

“Utilization of that submarine to counter China, I think is a natural expectation,” Caudle told reporters in a roundtable interview on Friday, when asked about the possibility of the nuclear submarine playing a role in countering China and reshaping the Korean Navy’s role in the broader East Asian region.

“With that type of capability, I think with United States would expect that partnership, again, working as an alliance together, to meet our combined goals on what the United States considers to be our pacing threat, which is China. I think to a large extent, Korea shares concerns with China as well, and so that capability should be part of that equation.”

Washington has been pushing allies to increase their defense spending and contribute to “collective defense” as it seeks to strengthen cooperation with allies amid an intensifying Sino-U.S. rivalry.

During their summit held in the southeastern city of Gyeongju, Lee also openly asked Trump to allow his country to secure nuclear fuel supplies for conventionally armed submarines to better track North Korean and Chinese vessels, saying it would ease the operational burden for U.S. forces.

Given the strategic value of a nuclear-propelled submarine, which he said brings “a whole different level of capability for deterrence,” the top U.S. naval officer said operating such a vessel will likely put more responsibility on the Korean Navy, not only regionally but on a global level.

“As they say in the movie ‘Spider Man,’ with great power comes great responsibility. I think there will be a responsibility for Korea to deploy those submarines globally and move away from just being a regional navy to a global navy,” Caudle said.

When asked about where the envisioned submarine will be built — whether in Korea or in a U.S. shipyard acquired by Korean conglomerate Hanwha as Trump wrote on social media — the U.S. naval chief said it is a matter that should be directed to the White House.

But even with the nuclear submarine project set aside, Caudle underscored the need for a strong partnership between Korea and the United States against China’s gray zone activities, based on a peace through strength model.

“We see this type of activity around the globe, and we are very concerned about it. That’s why our partnership with Korea is so important. There has to be a strong deterrence mechanism, or that type of activity between our two countries,” he said. “It’s my earnest goal with U.S. Seventh Fleet and U.S. Pacific Fleet and other joint force partners, along with Korea, to assert that that’s not going to be tolerated.”

Against such a backdrop, Caudle said conducting combined naval drills in international waters in the Yellow Sea to counter China’s threats is “certainly not off the table,” without further commenting on operational details. Currently, such exercises are mostly conducted in the eastern and southern waters off the Korean Peninsula.

The American nuclear-powered USS Vermont, a Virginia-class attack submarine, arrives at a naval base in Busan on Monday to replenish supplies. [YONHAP]

The American nuclear-powered USS Vermont, a Virginia-class attack submarine, arrives at a naval base in Busan on Monday to replenish supplies. [YONHAP]

Caudle, whose trip to Korea includes visits to shipyards here, anticipated Korea to “prominently” play a role in helping bolster the U.S. shipbuilding capacity.

While noting that legal hurdles exist for cooperation on combat ships, he said supply ships, auxiliary ships, consul tankers and car carriers are some types of vessels the two countries can work together on “right away” with little restriction.

When asked about North Korea’s move to build up its naval capabilities, Caudle noted that while the North is not a naval threat for the United States, keen monitoring is necessary to fend off its activities considered as threats to South Korea. He also mentioned underwater drone technology as one area that requires countermeasures.

“I am concerned with the use of unmanned capabilities under the sea, on the sea and above the sea. It is something we have to watch very closely and build the correct countermeasures to make sure we’re not impacted by those evolving technologies.”

On whether U.S. Forces Korea (USFK) or the South Korean military would intervene in a hypothetical China-Taiwan military conflict, Caudle spoke cautiously but did not rule it out.

“When there’s a conflict between peer powers like China and the United States, and any type of conflict like that, those things are typically what I would say, in my terms, ‘an all-hands-on-deck’ type of venture,” he said.

“During any kind of conflict, there’s always opportunistic things that third parties can be doing while you’re in conflict with another party. And so there, that’s the time when assurance and deterrence and peace through strength is extremely important. So that’s why you have to be prepared for that. So, I wouldn’t say what it would look like specifically, but I’m sure there would be a role.”

About trilateral cooperation between South Korea, the United States and Japan, Caudle said, “I started as a commander back in the 2004 timeframe and all the way up through commanding the Pacific submarine force, I’ve watched the relationship between Korea and Japan grow and United States being right along there with them through our trilateral agreement.”

“I know there are challenges between Korea and Japan, and sometimes those can manifest themselves, and they can cause some fragility in that relationship, but I think our militaries need to rise above that, and stay the course in operating together,” he said. “It’s in our best interest to do that, and I don’t see that stopping, and I’m very proud, actually, of Korea’s commitment to that.”

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