On Yeonpyeong island, Chae Jae-geun gazes through the thick fog towards North Korea’s heavily fortified southern coastline 12km away, too scared to venture out into the disputed waters where he usually goes crabbing.
“We are all worried about the current situation. Since we were bombed 10 years ago, we are still rattled by any sound of gunfire,” said Mr Chae.
The 60-year-old fisherman was referring to North Korea’s shelling of the island in November 2010 that killed two civilians and two marines, one of the deadliest attacks on South Korea since the end of the Korean war.
Mr Chae’s trepidation reflects the anxiety that has descended across many in South Korea. They fear that North Korea dictator Kim Jong Un is embarking on his latest cycle of military provocations, which experts believe are ultimately aimed at gaining leverage over US president Donald Trump.
Last week North Korea blew up the inter-Korean liaison office in the border city of Kaesong, destroying what had been a de facto diplomatic outpost for communication between Pyongyang and Seoul. The explosion also severely dented hopes for the rapprochement brokered in 2018 between Mr Kim and Moon Jae-in, the South Korean president.
Before the dust had settled from the blast at Kaesong, Pyongyang’s propagandists, who have complained about non governmental organisations sending anti-Kim material into North Korea, warned that its military planned to re-enter border areas that were disarmed after the 2018 inter-Korean Comprehensive Military Agreement.
North Korea specialists, including former US intelligence agents and advisers to the South Korean military, said that Pyongyang appeared to be returning to military provocation in an attempt to reset negotiations with Washington and push for an easing of crippling economic sanctions.
Talks have been stalled despite three meetings in two years between Mr Trump and Mr Kim.
Sue Mi Terry, a former CIA analyst, expected more North Korean actions this year, including against the US. She said the attack on the liaison office was merely the “opening salvo”.
Analysts expect the next phase of incitements to once again be targeted at South Korea. That would create a dilemma for Mr Moon, who has staked his presidential legacy on a long-term movement towards peaceful unification with North Korea.
“There are lots of discussions going on whether to respond to North Korea assertively or not,” said Jina Kim, an analyst at the Korea Institute for Defense Analyses, a think-tank with close links to the South Korean military. “[Any] action that we are going to take is going to be proportional to what North Korea does.”
However, any reaction from South Korea is unlikely to derail Pyongyang’s plans to pressure the US, said Go Myong-hyun, a research fellow at the Asan Institute for Policy Studies in Seoul.
“The end destination for that road map is going to coincide with the November presidential elections in the US,” he said.
Bruce Klingner, a former CIA officer who studies North Korea, said Mr Kim was attempting to destabilise Mr Trump’s election campaign in an attempt to improve its negotiating position.
“Pyongyang’s repeated references to the campaign, which I do not remember occurring before, suggests the regime believes it has leverage over Trump,” he said.
Experts diverge on whether the dictator will test long-range missiles or nuclear weapons, which would break his self-imposed moratorium that followed his first summit with the US president in Singapore in 2018.
Many weapons experts believe the North Korean military must run further tests before fully proving the capability of its intercontinental ballistic missiles, raising the likelihood of such a test.
A softer approach might involve testing submarine-launched ballistic missiles into the Sea of Japan — which South Korea calls the East Sea — or the unveiling of a new weapon at a military parade in the capital.
Still, there were fears that any military adventurism meant “they might fire something at South Korea” creating a “high chance” of miscalculation or accident, said Mr Go.
Amid this risk, at Yeonpyeong — which is just 100km from Seoul — several thousand South Korean troops have been put on high alert.
“We have heightened our guard and are conducting our drills with more urgency,” said Shim Sung-bo, a navy captain patrolling the area.
Im Yong-kwon, another fisherman in his sixties who witnessed the 2010 shelling, said he was used to North Korea’s threats but hoped Pyongyang was not provoked into action.
“Things were good with the rapprochement but the situation has suddenly become worse,” he said. “If they bomb us again, this may lead to war.”