Murtadha al-Tameemi, 24, is an Iraqi software engineer for Facebook who lives and works in Seattle. Most weekends he drives for three hours across the border into Canada to visit his family – his mother and two brothers – who live in Vancouver. That is, until now.

Since Donald Trump issued an executive order blocking the immigration of people born in seven predominantly Muslim countries including Iraq, al-Tameemi won’t be able to leave the US because he might not be allowed back in, even though he has a working visa (H1B). Nor will his family be allowed to visit the US.

“It’s pretty upsetting,” he told the Guardian. His family fled Iraq as refugees and spent two years in Jordan before settling in Canada in 2015. “Ever since then I’ve made a point to spend as much time with them as I can, because we missed out on a lot of each other’s lives.”

Murtadha Al-Tameemi, 24, is an Iraqi software engineer for Facebook who lives and works in Seattle. Photograph: Murtadha Al-Tameemi

He was in Vancouver attending the opening night of his younger brother’s first play when he received a “frantic call” from his lawyer last week telling him to return to the US immediately, before the executive order was signed. He’s now back in the US and has no idea when he’ll next see his family.

He’s particularly upset that this action has been taken in the name of preventing the terror groups his family escaped from.

“It adds insult to injury when people talk about excluding people like me as if we are a threat to this country when we have fled the very same things this country is fearing – whether Isis or al-Qaida – we have been the victims of their actions.”

Al-Tameemi is one of many people born in Iraq, Iran, Libya, Somalia, Sudan, Syria and Yemen affected whose lives have been torn apart by the executive order.

The ban dealt a blow to the technology industry, which relies heavily on foreign-born software engineers. Not only have families such as al-Tameemi’s been separated, but many visa holders are now afraid to leave the United States in case they are refused re-entry and detained.

Sanaz Ahari Lemelson, director of product management at Google. Photograph: Google

The family of Sanaz Ahari Lemelson, director of product management at Google, is facing a similar dilemma. Ahari Lemelson is a Canadian citizen originally from Iran who has a green card to live in the US.

She is also 37 weeks pregnant and was looking forward to having her parents, who live in Vancouver, travel to the Seattle area to attend the birth of their grandson. “That’s all up in the air now,” she said.

“It’s very disturbing. I have lived here for 12 years and consider it my home. I never realised this [executive order] could apply to my family,” she said.

Ahari Lemelson, who at 23 was one of Microsoft’s youngest ever lead product managers, could also face challenges returning to the US if she were to visit her parents. As confusion and chaos erupted in airports across the country on Saturday, senior US administration officials said that if green card holders from the identified Muslim-majority countries were traveling abroad, their return would be considered on a “case-by-case basis”.

“At the moment folks with green cards are going through hours of secondary screening, which basically means that my rights as a green card holder have been revoked and at best I’m a second-class citizen,” she told the Guardian on Sunday. “While it’s better than a ban, it’s not back to the rights I did have.”

To think that my daughter who calls them grandma and grandpa would be denied the ability to see them is heartbreaking Sanaz Ahari Lemelson

“My father is in his 70s, my mother is in her 60s and to think that my daughter who calls them grandma and grandpa would be denied the ability to see them is heartbreaking,” she added.

Anahita Moghaddam was born in Iran, is a German citizen and has lived in the United States since the summer of 2010. Also a green card holder, she is a Buddhist and runs a coaching practice to teach mindfulness and compassion to individuals and companies, many of which are based in Silicon Valley.

Anahita Moghaddam was born in Iran, is a German citizen and has lived in the United States since the summer of 2010. Photograph: Anahita Moghaddam

Since Trump’s executive order, Moghaddam’s lawyer has advised her not to leave the country.

“It feels absurd that I am affected by this ban to filter out terrorists. I cannot get my head round it. This is not the way to counter terrorism, it’s just creating separation and anger,” said the 34-year-old, who lives in New York.

This is not the way to counter terrorism, it’s just creating separation and anger Anahita Moghaddam

“The fact that I’m not even a practicing Muslim is ironic,” she added. “My job is helping Americans and American companies achieve higher levels of wellbeing and happiness.”

It’s not just families that are being torn apart by the executive order, but companies. Husayn Kassai is the Iranian CEO and co-founder of identity verification startup Onfido. He founded the company in 2012 after graduating from Oxford University in 2013 and expanded to the US in 2015, setting up a San Francisco office.

Although Kassai has a green card, he needs to renew it within a year. Meanwhile, two of the 10-strong team in the US are also Iranian and have working visas, while his London-based co-founder, Eamon Jubbawy, is of Iraqi origin. The executive order creates a lot of uncertainty for key staff members in the business.

US travel ban - a brief guide The executive order signed by Donald Trump suspends the entire US refugee admissions system, already one of the most rigorous in the world, for 120 days. It also suspends the Syrian refugee program indefinitely, and bans entry to the US to people from seven majority-Muslim countries – Iran, Iraq, Libya, Somalia, Sudan, Syria and Yemen – for 90 days. The order has prompted a series of legal challenges, while thousands of Americans have protested outside airports and courthouses in solidarity with Muslims and migrants.

“We didn’t expect this. The one thing Trump has is a little bit of business experience, so we thought he’d respect business and put the economy first,” he said.

“The great irony is we’re an identity verification company,” he said. “We are helping to combat some of these issues around security.”

Foreign entrepreneurs planning business trips to the US are left in a similar limbo.

Maz Nadjm, 43, is a British citizen born in Iran and the founder of SoAmpli, an award-winning startup that helps companies integrate their sales and marketing departments. He travels back and forth to the US several times a year to meet investors and clients and has previously lived and worked in Silicon Valley. However, his dual citizenship means he’s not sure he’ll be allowed to visit Atlanta in February to meet with clients.

“This sucks, as my American colleagues would say. I feel like a second-class citizen, and it’s anti-entrepreneurial. I’m trying to add value to the economy. I’m paying salaries, I’m paying tax,” he said.

It’s anti-entrepreneurial. I’m trying to add value to the economy. I’m paying salaries, I’m paying tax Maz Nadjm

Ahmed Elmurtada from Khartoum in Sudan is the Middle East regional director of global startup community Startup Grind. He was due to attend the organization’s annual conference in Silicon Valley in February, for the second year running. He was approved for a visa to visit the United States last week – before Trump’s bombshell executive order.

“Things are now very confusing and scary,” he said, speaking on the phone from Khartoum.

The blocking of immigration from Sudan was particularly shocking to Elmurtada, given that earlier this month the United States announced the end of a 20-year economic embargo in the country.

“People were getting very excited that finally Sudan could get the benefits of doing business with the United States,” he said.

Alas, the excitement was short-lived.

“Now, just because you are Sudanese, you can’t get what you deserve. It’s unfair and it’s very depressing.”