On Tuesday, Mr Trump released a statement shaming Ms Omar for leaving Somalia, where she was born before fleeing to the US as a refugee. The former president's statement was filled with lies and right-wing conspiracy theories disparaging the congresswoman.
"Congresswoman Ilhan Omar should apologize for marrying her brother, committing large-scale immigration and election fraud, wishing death to Israel, and for essentially abandoning her former country, which doesn't even have a government — Exactly what she'd like to see for the United States," Mr Trump said in the statement.
Ms Omar did not marry her brother. That idea was popularised by a former GOP operative Anton Lazzaro, who claims he used DNA matching from a straw used by Ms Omar's ex-husband to prove he was actually her brother. Mr Lazzaro has produced no verifiable proof of his claims and is currently awaiting trial after a grand jury charged him with 10 counts of child sex trafficking.
There is also no evidence that Ms Omar committed fraud of any kind, nor did she ever wish death to Israel.
Ms Omar was born in Somalia in 1982 and moved to the US with her father and siblings in 1995 through the use of asylum. The congresswoman leaving her home country and moving abroad is no different than any other immigrant, including Mr Trump's wife, who was born and raised in Slovenia.
Mr Trump made his statement amid an ongoing spat between Ms Omar and extremist GOP Congresswoman Lauren Boebert, who was filmed making Islamophobic remarks about her colleague during an event.
Ms Boebert claimed Ms Omar was part of a "Jihad Squad”, referencing the Islamic concept of spiritual or holy conflict. She also claimed that a Capitol police officer who entered an elevator with the two women "had fret all over his face" when he saw Ms Omar.
Well, she doesn't have a backpack. We should be fine," Ms Boebert claims she said, suggesting Ms Omar might be a terrorist carrying a bomb.
Ms Omar said the event never happened and claimed that not only did Ms Boebert never say those words, but that the congresswoman refuses to even look at her when they pass each other. She then pressed House Speaker Nancy Pelosi and House Minority Leader Kevin McCarthy to censure Ms Boebert for her comments.
"Normalising this bigotry not only endangers my life but the lives of all Muslims," she said.
Ms Boebert faced social media and political backlash for her comments and issued an apology to "anyone in the Muslim community I offended with my comment about Rep. Omar." She also said she planned to call Ms Omar and discuss the comments with her.
The call was apparently volatile and ended with Ms Omar hanging up on Ms Boebert.