SEOUL—The possibility of a military confrontation between the U.S. and North Korea is dominating headlines across South Korea, but in the streets of Seoul, concerns about a North Korean missile or nuclear test—or even a pre-emptive U.S. military strike—are drowned out by the rhythms of daily life.

“North Korea makes threats, but they will not do it. No way,” said Yu Jeom-soon, a 59-year-old shop worker in downtown Seoul, who sat on a chair drinking tea on Friday during a spring downpour.

“I used to feel worried in the past, but now I think, if people here die, then people in North Korea will also die, so I don’t think they will do it,” she said.

In the past few days, the rhetoric has grown more heated from all sides. Meanwhile, satellite imagery shows signs that North Korea may be preparing a nuclear test ahead of its biggest holiday, the birthday of the country’s founder, Kim Il Sung.

Chinese Foreign Minister Wang Yi on Friday said Beijing was urging all sides to avoid inflammatory or threatening statements and deeds, adding that no one would win in a war.