Women practice calligraphy at the Korean American Senior Center of Flushing, New York. Most at the center hope that diplomacy will resolve the current tensions between the US and North Korea

Memories of war haunt elderly Koreans in New York when they think about the gathering nuclear crisis between their homeland and the country they adopted in search of the American dream.

Four million people perished in the 1950-53 Korean War between a US-backed South and China-backed North Korea. It was a bloodbath that ended in stalemate and today lies behind diplomatic panic, depressed markets and frayed nerves.

"We are seniors, all the people, we have experience of war," says Byong Lee, 81, at the Korean American Senior Center of Flushing, New York where he is one of 300 to 350 elderly Koreans who take lunch Monday to Friday.

"They all went to the army and things like that, they know North Korea and that idiot dictator."

The US atomic bombs dropped on Japan at the end of World War II killing more than 200,000 people linger in the minds of those who come here to play ping pong, read the newspaper or take English classes.

The cost of war they know. The cost of nuclear war, according to those who were children when Nagasaki and Hiroshima were bombed, would be beyond catastrophic.

"He's crazy," says 75-year-old Wonil Lee of North Korean leader Kim Jong-Un. Ask everybody the same question and you'll get "almost the same answer," he says.

But one retired nurse dashing off to a folk-singing class isn't sure Kim's the only one.

She laughs when asked how President Donald Trump is handling things. "Everybody worries how he talks about everything on Twitter," she says conspiratorially, refusing to give her name. "Some say he's just like Kim Jong-Un."

- 'Who knows' -

Kwang Sup Jang (R) shows a photo of himself as a chaplain in the South Korean military as Wonil Lee (L) looks on. Some 100,000 people of Korean descent live in New York City, part of a Korean diaspora of 1.7 million living in the United States

Around 100,000 Koreans live in New York City, most of them in Trump's childhood borough of Queens. Around 1.7 million of Korean descent live in the United States -- the second biggest Korean diaspora in the world after China.

In the streets around the center, currently in the basement of a church but poised to relocate to a larger, multi-million-dollar premises, Korean signs are everywhere -- outside a pharmacy, on a repair man's van, outside a medical clinic.

Wonil Lee, a Vietnam War veteran from the Korean military, is happy to offer a few choice words of advice for Trump, whom he calls the most powerful man in the world, to get the better of the 33-year-old Kim.

"Dollars!" he grins underneath a camouflage baseball hat near women taking a calligraphy class.

He wants to see a revival of the ping-pong diplomacy between the Nixon administration and China -- only this time the Korean version.

"America is a very rich country. I think if I was Mr Trump and American president I would say 'OK, how much do you want?'" he says.

"It's not going to work," interjects Byong Lee, shaking his head. After migrating to the United States in 1983 Lee ran a vegetable store, then a cheese shop and worked in asbestos removal before creating a manpower company.

Like others at the center Lee doubts the North Korean leader will follow through on threats to attack Guam.

"But he's an idiot so who knows?... If he does, he's gotta know he's going to die himself."

- 'Flap, flap, flap' -

Many at the Korean Community Services center would rather play Baduk, the Korean version of Go, than discuss politics

Neither does he have much confidence in the US president, who said Thursday his threat to rain "fire and fury" on North Korea maybe "wasn't tough enough."

"You can't believe him!" Byong Lee exploded. "Flap, flap, flap. He can say all he wants to... but the thing is, he really wants nuclear war?"

"He doesn't think what we think," he added. "What about us?"

Most of the retired Korean-Americans at the center prefer to talk about family, play ping pong and take singing lessons than discuss politics.

Others harbor residual hope for a billionaire president who grew up a 15-minute drive away.

"Hopefully he does what he says," said Susie, an elegantly dressed woman who declined to give her last name. "He's doing new things, so hopefully he's better."

The retired nurse worries most about those at home on the Korean peninsula. "They're kind of used to it -- 'oh my God here's the same thing again', but I'm kind of worried," she admitted.

"We've been talking the last 20 years and I wish that Trump would... do something about this guy," she said.

But what?

"I really don't know."