SALT LAKE CITY (NYTIMES) - Before sunrise each day, Ms Holly Hwang nestles her little girl into a carrier and bikes her to a day care centre.

It is a 16-kilometre slog, sometimes through rain or snow, before she reaches the warehouse where she earns US$9.52 (S$13.14) an hour operating a forklift. After clocking out, she rides back another 16km to pick up her four-year-old and head home.

The commute can be exhausting, but not compared with the gruelling journey that brought her here.

It started when she escaped from her native North Korea to China with the help of a smuggler, who then sold her into servitude, and marriage, to a stranger.

She fled once again and arrived in Salt Lake City with her child nearly three years ago - one of a dwindling number of North Korean defectors admitted to the United States in recent years.

"My life is settled and very safe in Utah," said Ms Hwang, 39, who hopes to learn enough English to become a truck driver.

North Koreans have been fleeing economic and political oppression by the thousands for two decades.

While most have ended up in South Korea, which grants them automatic citizenship, at least 220 have come to the United States since 2004, when Congress passed the North Korean Human Rights Act and opened the door to political refugees.

Now, though, a crackdown by North Korea on its border, along with the Trump administration's overall curbs on refugee admissions, has slowed new arrivals to a trickle.

President Donald Trump has made significant efforts this year to engage North Korea's mercurial leader, Mr Kim Jong Un, in hopes of halting the country's nuclear weapons programme.

His administration's limit on refugee admissions, analysts say - whether such a consequence was intended or not - has aided the North Korean leader in his attempt to slow the pace of defections from a country seen as one of the most repressive in the world.

Only one North Korean defector arrived in the United States in 2017; five have been admitted this year.

Supporters of the 2004 humanitarian law, which Congress reauthorised in July and Mr Trump signed once again into law, have expressed concern that the drop in arrivals dilutes any message to North Korea that the United States is committed to integrating human rights with national security.

"The fact they are working on a nuclear agreement doesn't take anything away from the fact Kim Jong Un is oppressing his people," said Mr Hans Van de Weerd, vice-president for United States programmes at the International Rescue Committee, one of the organisations that helps settle North Koreans in the United States.

The United States admitted 22,491 refugees from all countries in the fiscal year that ended Sept 30, the lowest number since the refugee resettlement programme was created in 1980 and less than half the number the government had said it was going to allow.

Last month, the government set the ceiling at 30,000 for the current fiscal year.

But 11 nations have been singled out for special scrutiny, based on security considerations, under what had initially been known as Mr Trump's travel ban.

North Korea is one of them, and the more stringent background checks have extended the time it takes for US agencies to process cases from North Korea. What once took months now takes years.

State Department officials have said that the current regulations require "extreme vetting" of nationals from a number of countries, and have not drawn any connection between the downturn in North Korean refugee admissions and the Trump administration's attempt to forge new political openings with Mr Kim.

The additional screening of North Koreans was, in fact, introduced when Mr Trump was at odds with the North Korean leader.

Analysts said North Korea's inclusion was likely intended in part to help fend off legal challenges to the travel ban that argued it was based on religion, since the other 10 countries included have Muslim majorities.

"The United States continues to prioritise the admission of vulnerable refugees," a State Department spokeswoman said in a statement.

The first nine North Korean defectors arrived in the United States in 2006. Entries were in the double digits each year until 2016, the year before Mr Trump took office.

Leaving the highly fortified country is notoriously difficult. North Koreans climb mountains, trudge through rugged terrain and cross rivers in their bids to escape. Even if they elude border agents and make it into China, the most common escape route, they risk being apprehended and repatriated by the Chinese authorities.

In recent years, the vast majority of escapees have been women, often sold into forced marriages in China. Others are trafficked for sex or cheap labour.

Ms Joanna Kim, who arrived in Salt Lake City last month, said that the Trump travel ban and the extra vetting that followed are to blame for her two "very hard and long" years parked in an immigration detention facility in Bangkok.

Other North Koreans who had applied to come to the United States gave up, she said, because the protracted wait became too stressful. They could reach South Korea in a matter of weeks.

Many have no contact at all with the loved ones they left behind. Families there cannot exchange letters in the mail; there is no Internet coverage.

Moreover, there are fears that North Korean authorities could exact retribution against families if it is discovered that their close kin live in the United States.

"To be living as a North Korean defector in America is the biggest treason to the country," said Mr Andrew Hong, executive director of the group Emancipate North Koreans, a non-profit that assists defectors in the Chicago area.

Those in touch with family in North Korea struggle to support themselves and those they left behind.

In contrast to the enormous success of South Korean immigrants and their descendants in the United States, most North Koreans, as a result of limited education and English, qualify only for low-paying work.

Mr G.D. Hwang, a defector who arrived two years ago, works at a factory by day and at a Walmart overnight. Every two months, he funnels cash to his family through an informal money-transfer network.

Staring sadly at a frayed print of a digital photo of his wife and two children, he said, "I am free but it's lonely without my family."

In her first attempt to reach China, Ms Holly Hwang, the single mother, was captured by North Korean border agents and delivered to a labour camp, where she harvested potatoes and collected wood.

If she talked to another detainee, she recalled, a guard might grab her by her hair and stomp on her. She was released when she fell gravely ill, she said.

"I was purple and blue and almost gone," she recalled, her eyes glassy with tears as she shared her story in a playroom at the International Rescue Committee as her daughter, Mee, resplendent in a shimmery pink Korean long dress, entertained herself nearby.

Ms Hwang and a sister eventually made it to China with the help of a broker, only to be sold off as brides to Chinese men who took them to different cities. They have not seen each other since.

Together with her baby from the forced marriage, Ms Hwang made the passage to Thailand in 2015 with the help of South Korean guides.

In Bangkok, mother and daughter were processed and on their way to the United States within six months - an unusually speedy transition.

Ms Hwang, who helps load goods with heavy machinery at a Mormon aid distribution centre, says her dream is to study business.

She is also striving to master enough English to pass a commercial driving exam. "You make good money as a truck driver," she said.

Like many North Koreans, she has found a South Korean church that provides her a sense of community and some financial support. But she still finds herself thinking often about home, she said.

"US life is better. North Korea is hell," she said.

But she added: "I'm lonely and miss my family in North Korea. If someone said they don't miss home, they're lying."