South Korean Soldiers at the Joint Security Area facing the North Korean side of the border. Photo: iStock

A war against North Korea “cannot happen” even if “the Korea-U.S. alliance breaks down,” Korea JoongAng Daily has quoted a key adviser to South Korean President Moon Jae-in as saying.

But Moon Chung-in, a presidential special adviser on foreign affairs and national security, said that Seoul is nervous about US bombers flying close to a strategic boundary with North Korea and worries about an accident or miscalculation that develops into a nuclear war. He also says there should be more input from South Korea on such flights.

“It is considerably worrisome if US strategic bombers cross the Northern Limit Line (NLL) and return without plenty of consultation with our government,” added Moon, who is also a professor emeritus of political science at Yonsei University.

The NLL is the de facto border with North Korea in the Yellow Sea.

Moon made his comments at a panel on how to resolve the Korean Peninsula crisis hosted by the East Asian Future Foundation in Seoul Wednesday. His remarks come after US President Donald Trump threatened to “destroy” North Korea if necessary last week at the UN General Assembly.

The US, on Saturday, flew its B-1B Lancer strategic bombers over international airspace over waters east of North Korea. This is the farthest north of the demilitarized zone (DMZ) it has flown this century, according to the Pentagon.

“There is concern that the biggest crisis could be an accidental or deliberate clash between North Korea and the United States,” Moon said, “which develops into a nuclear war rather than a conventional one.”