Here’s a link to CNN Fact Check regarding Omar’s past statements. In light of past comments, I understand Trump’s comments a bit more.
https://www.cnn.com/2019/07/15/politics/trump-falsely-accuses-omar-al-qaeda-fact-check/index.html
It is possible to argue that Omar was making light of al Qaeda’s crimes in suggesting that its name itself is what makes people recoil, or that she was implying that there is an equivalence between al Qaeda and the US army. But accusing her of praising al Qaeda is simply inaccurate.
Trump also made reference on Monday to another set of comments from Omar. In March, she told the Council on American-Islamic Relations (CAIR) advocacy group that average Muslim Americans need to “raise hell” to stand up for the civil liberties they had lost because “some people did something” on 9/11. Trying to quietly demonstrate good behavior is insufficient, she said.
And another on the Jewish issue:
Omar, along with Rep. Rashida Tlaib, D-Mich., the only other Muslim woman in Congress, have been criticized by Republicans and Democrats for comments about the Israeli government and the influence of pro-Israel lobbyists in Washington, and accused them of evoking anti-Semitic tropes.
Omar has apologized for some of her comments, but defended her criticism of the Israeli government.
WHAT OMAR SAID: In January, Omar was criticized for a (deleted) 2012 tweet where she said Israel “has hypnotized the world, may Allah awaken the people and help them see the evil doings of Israel,” after the 2012 conflict with Hamas in Gaza. She defended the comments, saying she was criticizing the military action by Israel.
A few weeks later, Omar was at a progressive event in Washington where she said pro-Israel activists pushed “allegiance to a foreign country,” in an effort to clarify her initial comments.
“I want to talk about the political influence in this country that says it is OK for people to push for allegiance to a foreign country,” Omar said, immediately prompting criticism that she was evoking stereotypes about “dual loyalty,” a trope seen as anti-Semitic but also associated historically with other immigrant groups.
(MORE: House to vote to condemn anti-Semitism in indirect rebuke)
In March, the House passed a resolution condemning anti-Semitism, racism and bigotry in response to Omar’s comments, though some Democrats were angry that it didn’t mention the congresswoman by name.
https://abcnews.go.com/Politics/president-trump-falsely-claims-rep-omar-praised-al/story?id=64349788