After US President Donald Trump told four US congresswomen of colour to “go back” to the countries “from which they came”, some Americans have been sharing their own experiences of hearing that kind of language.

One BBC reader said the incident was reminiscent of an experience on a London bus in 1975 when a white woman accusingly said “you foreigners, why don’t you go back to your country?”

“Yes, we were foreign students, we felt petrified, yes, we immediately got off the bus on the next stop,” said the reader, who did not wish to have their name used.

“Racism is ugly, ignorance and hurtful, and unfortunately it is everywhere,” they continued.

In a three-tweet thread on Sunday, Mr Trump accused the four Democrats of “viciously” criticising him and the US.

Three of them on Friday spoke out about conditions in a migrant detention centre they had visited, describing alleged mistreatment happening “under American flags”.

Although the president did not name them, it was clear he was referring to Alexandria Ocasio-Cortez, Rashida Tlaib and Ayanna Pressley, who were born in the US, and Ilhan Omar, who came to the US as a refugee aged 12.

His remarks have sparked condemnation in the US and abroad. UK Prime Minister Theresa May said they were “completely unacceptable”.

• Theresa May condemns Trump’s ‘go home’ remark

Lots of other BBC readers have been telling us about their experiences, in the US and elsewhere.

Larry Christopher Bates writes from Bloomington, Indiana, that he has been told to “go back to Africa” so many times and at such an early age that he cannot recall the first occasion.

Mr Bates, who was born in Indiana, calls it “one of the first lines of insult from white nationalists”.

Iain Tyson says that when he was stopped while driving by a Los Angeles police officer, the officer heard his British accent and – using an expletive – told him to go “back to where you came from”.

He said that during his travels in the US, he has frequently been told: “If you don’t like it, why don’t you go back to where you came from?”

Juan Oliveros Müller, who is a Venezuelan living abroad in Estonia for the past seven years, said that when he went to renew his legal residency ID, he was told by an officer to “go back home since I’m a mañana person’ (tomorrow person)”.

Mukhtar Barde of Illinois said that when “white Americans” tell him to go home, he reminds them that Native Americans were the first people in North America.

“You would be surprised how many of the same white men then start telling me that they are part Native Americans and belong here.”

Moroccan Abdel Tazi, who has been living in the UK for the past five years, said that when he took a driving test, the instructor began every sentence with “in this country…”

“At one point, I took a wrong turn and he started shouting at me ‘I don’t know where you’re from, but this is wrong!! Can you not tell your right from your left in your country? You should probably go back’.

“Without saying anything, I stopped the car, got out and got a taxi home. I was upset for the rest of that day.”

Littlebird Arzabal says her family are indigenous and have been living in New Mexico since before it became a US state.

“The white kids would yell at us to go back to Mexico. They had someplace to go back to, we didn’t,” she says.

And on Twitter

Tweeting from Kansas City, Victor Hwang wrote that he has been told to “go back to where you came from” his whole life.

He said it makes him “sad” that “99% of Americans don’t fully appreciate how special this nation is”.

“I’m the son of immigrants, a woman who escaped communism, a father who pulled himself up from nothing.

“I get this nation in a way that many people never will. I love America and everything it means for the world. And I belong here.”

Neera Tanden of the liberal-leaning Center for American Progress said that 2016 was the first time that people on Twitter began telling her “to go back to India” and sent her photos of poverty in India.

“I was born here. But they saw me as less American because I am brown. Now Trump parrots them. That is what we fight.”

History of the phrase

Dr Michael Cornfield, an associate professor of political management at George Washington University who studies political rhetoric, says “exclusionary” words like these date back to before America’s founding and have arisen at different points various immigrants groups arrived in waves.

In the early 20th Century, Italians, Irish, Poles and others were villainised by politicians amid concerns about economic stagnation.

In the 1910s, President Woodrow Wilson “was an open segregationist that wanted the races kept separate,” says Mr Cornfield.

But in the Vietnam era, as politicians became more vulnerable on a national level to charges of racism, the calls for expulsion were normally based on differences in political opinion, rather than race.

“America, love it or leave it,” was a popular bumper sticker, and a phrase spoken by many lawmakers.

The slogan, he says, “was a test of loyalty to the flag and to the nation” but was typically “not racial.”

President Trump’s defence

He has consistently rejected the accusation that he is racist and on Monday he accused the four congresswomen themselves of stoking racial division.

Later he told reporters that he had no regrets about his comments and many people agreed with him.

“These are people that hate our country. They hate it, I think, with a passion. If you’re not happy here, you can leave,” he added.

“So all I’m saying is if they want to leave, they can leave.”

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