PAEKRYEONG ISLAND, South Korea — Kong Da-hee, a chubby fourth-grader with her quick eyes framed by steel-rimed glasses, says she has a recurring dream when the evening television news reports North Korea’s nuclear threats.

“I see this imaginary North Korean island in my dream. It gets bigger and bigger as it floats closer and closer to our island. It reaches our shore and kidnaps our neighbors to North Korea,” the 12-year-old says. “I wish we were far away from North Korea.”

Paekryeong Island, where Kong lives with her mother and nine-year-old brother, is South Korea’s northernmost island, flung deep into North Korean waters. Its residents skirt the tense western sea border between the two Koreas and sail 220 km to reach mainland South Korea. In contrast, North Korea lies only 16 km north, and when the weather is clear, the fishermen here like to say, “It looks so close you can stretch your arm and touch it.”

Paekryeong’s location enables South Korea to control rich fishing grounds near the North. But it also makes the 45-sq. kilometer island vulnerable to North Korea’s military threat. It could be the first target of artillery attacks in case of war.

On Paekryeong, the peaceful life of fishermen co-exists with military tension.

Crab and anchovy boats cut the gray-blue waters, sprays of salt water breaking over their bows. Below wind-battered coastal bluffs, a herd of seals loll in the water. Jet-black cormorants skim the water and dive for fish.

Choi Dae-won, a 46-year-old fisherman, says his island is “blessed by God.”

Paekryeong islanders were preoccupied with mending their nets and selling dishes to occasional tourists. They were so used to North Korean threats that they shrugged off news about the North’s suspected nuclear weapons development, and instead preferred to talk about the menace of Chinese poachers on their rich fishing grounds.

To outsiders, however, military tension is a unique feature of Paekryeong, South Korea’s most militarized island. There is almost one marine to each civilian in this island of 6,500 people.

Warships follow fishing boats like shadows, ensuring they don’t stray into communist waters and protecting a disputed sea border from North Korean provocations.

Paekryeong’s hills are pockmarked by gun positions and trenches and capped with radar stations and observation posts, providing South Korea with invaluable forward surveillance of North Korea’s military.

The whole island is cordoned with tall wire fences manned by marines. All villages are built behind hills to make it difficult for North Korean artillery to target them. Each village has underground shelters. The marines have built underground bunkers where they could dig in if North Korea showers the island with missiles and artillery shells in the initial hours of a war.

“Our strategy is to wait out and counterattack as soon as we can,” says marine 1st Lt. Choi Jae-rim, whose platoon mans an observation post on a 184-meter peak. Downhill, a phalanx of rusty steel obstacles jutted from the submerged beach to thwart North Korean landing craft. The North keeps a formidable force along its shoreline opposite Paekryeong: Two army divisions and a regiment, four air fields, batteries of missiles, multiple rocket launchers, shore guns and artillery.

“Our island lies right under North Korea’s nose,” says Maj. Joo Jong-hwan. “We give North Korea a big headache.”

The daily, five-hour ferry trip to Paekryeong takes a detour, because islands and waters held by North Korea cut deep into the beeline between mainland South Korea and Paekryeong. On board, visitors listen to a military-issued videotape warning them about minefields on the island.

The waters along the western sea border are the most volatile portion of the inter-Korean frontline. Lured by rich fishing grounds, North Korean boats often cross the border and South Korean navy ships chase them away. The navies of the two Koreas fought deadly skirmishes in the western sea in 1999 and 2002.

“I think about the North Korean danger whenever soldiers practice shooting,” says Kong, the teenager. She rides a bicycle along village alleys, past a marine guard post that checks traffic at a wharf.

In the 1970s, North Korean jets brazenly flew into the sky over Paekryeong, islanders say. High school students and housewives were required to join regular military training involving live ammunition. During air raid drills, they were mobilized and assigned to trenches. The rigorous civil defense training subsided as South Korea’s military power grew and relations between the two Koreas eased, especially after a historic summit between the two Koreas in 2000.

“Today I am more concerned about the Chinese boats than North Korea,” says Lee Yong-nyo, 67. “They come by the hundreds. They catch anything, everything and deplete our sea.”

Lee fled her North Korean hometown near Paekryeong during the Korean War. From this island, she hoped she would return home quickly once American-led UN forces liberated the communist North. That never happened. She left a brother and three sisters in the North, and she has never heard from them. “North Korea is right over there,” she said, gazing at the fog-shrouded North and wiping her ruddy face with her wrinkled hand. “But to me, it is a very distant place.”