Long before President Donald Trump turned up the heat on four Democratic congresswomen of color, saying they should 'go back' to their home countries, hateful rhetoric and disinformation about the self-described squad was lurking online. Racist, inflammatory and inaccurate content has circulated on far right blogs, news sites and social media accounts about Rep. Ilhan Omar of Minnesota and her three freshman colleagues since they ran for public office. With his tweets and harsh comments, Trump has elevated that rhetoric, playing into a conspiratorial feedback loop that reared its head repeatedly during his campaign and presidency. Trump rose to conservative prominence by falsely claiming former President Barack Obama, the first black president, wasn't born in the country. Since then, he has promoted claims and memes that originated in the darkest corners of the internet while fueling new ones of his own. His latest targets are Omar and Reps. Alexandria Ocasio-Cortez of New York, Ayanna Pressley of Massachusetts and Rashida Tlaib of Michigan. In his Sunday tweets , Trump claimed, without identifying the women by name, that the minority legislators 'originally came from countries whose governments are a complete and total catastrophe.' He suggested they should 'go back' to those 'totally broken and crime infested places,' even though three of the four were born in the U.S. and all are U.S. citizens. He has since questioned the women's allegiance to their country, accusing them of hating America and promoting terrorism while suggesting they should leave America if they're unhappy here. For some, the Republican president's tweets were shocking. But for others, they were just an average day on Facebook or Twitter, where allegations that Omar was not legitimately elected, is not a U.S. citizen and committed immigration fraud have festered in far right chatrooms, blogs and social media sites since she was elected to the Minnesota House of Representatives in 2016. 'This is the agenda of white nationalists, whether it is happening in chat rooms or it's happening on national TV,' Omar said this week. 'And now it's reached the White House garden.' Omar was born in Somalia and immigrated to the U.S. as a refugee in 1995 when she was a child. She became a U.S. citizen in 2000 at age 17. The rumors about her have been spread by dozens of conservative social media figures and bloggers, including Michelle Malkin and Laura Loomer, the latter now banned from Facebook. In February, self-described far right social media influencers Jacob Wohl and Loomer flew to Minneapolis, where they provided live updates on Instagram, Twitter and Facebook of their trip to 'investigate' Omar's past and immigration status. Even seemingly everyday citizens have taken to social media to upload their own theories on Omar's background, with one Minnesota woman posting a video months ago on Facebook sharing 'proof' Omar is not a U.S. citizen. The video has been watched more than 50,000 times. Trump also repeated a contested claim, characterizing as 'fact' that Omar had married her brother, before acknowledging that he really didn't know. 'Well, there's a lot of talk about the fact that she was married to her brother,' Trump said this week in response to a question posed by a conservative news outlet. 'I know nothing about it. I hear she was married to her brother. You're asking me a question about it. I don't know, but I'm sure that somebody will be looking at that.' Omar has described such allegations as 'disgusting lies.' She has declined to provide access to immigration records, birth certificates or other documents that could verify her family history. Omar, the biggest target of online vitriol among the four legislators, has made comments that raise eyebrows, including a remark this spring in which she referenced the Sept. 11 attacks by saying that 'some people did something.' She was also criticizing for asking a judge in 2016 to show leniency toward a man accused of trying to join the Islamic State. But other allegations have been provably false. Before they took office, for instance, Omar and Tlaib, the first Muslim women elected to Congress , were dogged by false online allegations that they were so anti-American they did not intend to take the oath of office. Others tried to delegitimize Omar in memes that falsely claim Obama resettled 70,000 Somali refugees in Minnesota in an effort to ensure her election. In fact, the state received 6,320 Somali refugees during the Obama administration. A similar inaccurate claim was later floated online about Iraqi refugees in Tlaib's home state of Michigan. Other comments by the women have been taken widely out of context. Around February, social media users and fringe sites began circulating an edited 2013 clip that they said showed Omar 'laughing' at al-Qaida and admitting to taking a 'terrorism' class. The full context of the 28-minute interview, originally broadcast on a local Minneapolis TV station, shows she was talking about a U.S. college course and was making a point about how the Arabic language had been hijacked by extremist groups to mean something negative. In the 2016 presidential election, Russians relied on a similar online playbook, deploying anti-immigrant and anti-Muslim rhetoric on Facebook, Instagram and Twitter in an effort to boost Trump's prospects. Racially divisive content was the biggest component of the Russian disinformation campaign, according to Ian Vanderwalker, counsel for the Democracy Program at the nonprofit Brennan Center for Justice. One Facebook post linked to a Russian agent, for instance, featured a group of women walking in headdresses and asked: 'What are they hiding?' 'A lot of it was fearmongering that was intended to mobilize right-leaning voters,' Vanderwalker said. 'Some of it was similar to or echoed themes in Trump's own campaign.' He predicted Russians would revive racially fraught social media content in 2020. Negative sentiment about the four congresswomen has migrated into more mainstream outlets recently. Last week, just days before Trump's incendiary tweets, Fox News host Tucker Carlson described Omar on his show as having 'undisguised contempt for the United States.' The president's comments, in turn, appear to have inspired even more negative online rhetoric, including a new batch of Facebook and Twitter posts that describe Omar as a 'terrorist.' Memes also have emerged calling the women 'anti-American' and 'enemies within.' One mock movie poster labels the women 'The Jihad Squad' and includes the tagline: 'Political Jihad is their game.' The attacks are part of a pattern for Trump, said Kathleen Hall Jamieson, a professor at the Annenberg School for Communication at the University of Pennsylvania and the author of a recent book about how Russian hackers and trolls influenced Trump's election. She pointed to Trump's birther claims against Obama, which she said suggested 'he doesn't belong here, he belongs somewhere else,' as well as Trump's unfounded claims in 2016 that Hillary Clinton and Obama were co-founders of the Islamic State group. Chants at the president's rallies — such as 'Lock her up!' in reference to Clinton or the newly minted 'Send her back!' refrain for Omar — emerge because Trump has cast the women as enemies of the nation, Jamieson said. The result, she said, is to discredit 'the loyalty, patriotism and ability to act on behalf of the U.S. of an elected official.' ___ Seitz reported from Chicago. Follow Seitz and Colvin on Twitter at https://twitter.com/AmandaSeitz1 and https://twitter.com/colvinj .