Democratic presidential candidates, led by Bernie Sanders and Elizabeth Warren, spoke out forcefully in defense of Rep. Ilhan Omar this weekend, after the president of the United States risked inciting violence against the Muslim congressperson by endorsing the false claim that she downplayed the September 11, 2001 terrorist attacks.

Those comments from the progressive Democratic senators contrasted sharply with House Speaker Nancy Pelosi’s initial failure to even mention that Omar, whose life has recently been threatened by a Trump fan, was the target of the president’s inflammatory tweet, which mixed video of her with harrowing images of the World Trade Center towers falling.

After a wave of criticism for those tepid remarks — which seemed to endorse the claim that Omar had somehow erred in failing to show “reverence” in how she referred to the 9/11 attacks — Pelosi called on Sunday for Trump’s tweet to be deleted and asked for security to be stepped up for Omar.

Pelosi was forced to take the threats to Omar more seriously by the fact that, as the weekend wore on, more and more Democrats followed the lead of Sanders and Warren, who denounced Trump’s tweet for its incitement against the Muslim representative rather than its use of 9/11 imagery.

Trump had propelled the smear campaign against Omar into overdrive on Friday night, taking his cues from Fox News and the New York Post, which stoked outrage by distorting a reference to the attacks that Omar made during a speech in support of a Muslim civil rights group.

The raw material for the manufactured outrage was video of Omar discussing the work of the rights group, the Council on American-Islamic Relations, or CAIR, in combating anti-Muslim bigotry after the September 11 attacks. The actions of those terrorists, she told supporters of the group, had led some Americans to associate everyone of that faith with terrorism. “For far too long,” Omar said, “we have lived with the discomfort of being a second-class citizen and, frankly, I’m tired of it, and every single Muslim in this country should be tired of it. CAIR was founded after 9/11 because they recognized that some people did something and that all of us were starting to lose access to our civil liberties.”

Although Omar’s reference to the attackers having been Muslims was vague, it was not, as her enemies claimed, flip or dismissive — nor was it intended as a description of the attack itself.

The video posted on Twitter by Trump clipped out Omar’s passing reference to the attacks — set to unsettling music and played on a loop with footage of the attack in New York — and treated it as if it were proof that Omar had described the massacre as unimportant. Trump’s all-caps caption for his video, “WE WILL NEVER FORGET,” was echoed in a closing on-screen title, which read: “September 11, 2001. WE REMEMBER.”

In addition to the false accusation against Omar, that closing invocation to remember was an accidental reminder that Trump had revealed, during the 2016 campaign, that he does not, in fact, recall the events of that day clearly. By insisting, against all evidence to the contrary, that he remembered watching on television as “thousands and thousands” of American Muslims in New Jersey cheered the collapse of the towers, Trump betrayed that he was either genuinely confused and believed that something he had imagined actually took place, or that he was willing to smear an entire faith community by pretending that their behavior matched his delusion.

The gross distortion of Omar’s actual comments was initiated by a fringe Shiite Muslim cleric in Australia, Mohamad Tawhidi, whose embrace of far-right myths about Sunni Muslim plots to destroy Western civilization has made him a favorite of Australian nativists and tabloid journalists working for Rupert Murdoch. Tawhidi tweeted video of the congressperson, edited from a Daily Caller edit, along with an inflammatory lie: that “Omar mentions 9/11 and does not consider it a terrorist attack.”

That false claim, along with another lie — that Omar sought “to justify the establishment of a terrorist organization (CAIR) on US soil” — was amplified by Rep. Dan Crenshaw, a Texas Republican.

Crenshaw’s tweet then formed the basis for a segment broadcast into the White House during the Wednesday morning edition of the president’s daily briefing, a.k.a “Fox and Friends.”

The claim from Fox, that Omar’s comment “trivializes September the 11th,” was followed by a New York Post cover showing the towers under attack, which seems in turn to have inspired Trump’s video. So a false claim made about Omar by a fringe figure in Australia, who owes his celebrity to journalists working for Rupert Murdoch, was then amplified by Murdoch’s American television network and Murdoch’s New York tabloid, both of which shape the American president’s worldview.

Omar said in a statement released late on Sunday that the incitement had produced a response from Trump’s followers. “Since the President’s tweet Friday evening, I have experienced an increase in direct threats on my life—many directly referencing or replying to the President’s video,” she wrote.

The objection of Trump’s defenders, that the president and like-minded Republicans were merely responding to Omar’s words, is undercut by the fact that his video seems to echo a bigoted internet meme displayed on a poster in West Virginia’s Capitol last month, which was made well before she said anything at all about 9/11.

The message of that poster, and the barely concealed subtext of attacks on Omar by Trump and other Republicans, is that the mere presence of a Muslim woman in Congress is proof that Americans have “forgotten” the terror attacks — by failing to embrace bigotry.

After Sanders and Warren spoke out against Trump’s video on Friday night, their comments were followed throughout the weekend by statements expressing varying levels of support for Omar from almost all of the leading contenders for the Democratic nomination.

Former Rep. Beto O’Rourke was criticized for failing to mention Omar in his first tweeted comment. Hours later, his campaign shared video of him describing Trump’s tweet in South Carolina on Saturday morning as “an incitement to violence against Congresswoman Omar, against our fellow Americans who happen to be Muslim.”

Perhaps the least supportive comment came from Sen. Kirsten Gillibrand, whose statement seemed to accept the Republicans’ false claim that Omar was somehow guilty of “minimizing” the pain of the attack’s victims or families.

Sen. Cory Booker, who initially released no statement, denounced Trump’s attack on Omar in an interview with CBS News recorded on Saturday and broadcast Sunday morning.

Former Vice President Joe Biden, who responded to Trump directly last week when the president mocked him, was the only likely candidate to offer no comment. Biden’s silence was made even more obvious by the fact that another possible contender who has yet to decide on a run, Stacey Abrams, did release a strong statement of support for Omar.

Pelosi’s first mild rebuke of Trump was far less supportive of Omar than statements from several of her colleagues, including Rep. James Clyburn, the Democratic whip.

Rep. Jerry Nadler, chair of the House Judiciary Committee, told CNN on Sunday that he was not troubled by Omar’s reference to the attacks, as Pelosi seemed to be, and lambasted Trump for taking a post-9/11 grant meant to aid small business owners in the area. “He stole $150,000 from small businessperson” Nadler said. “He has no moral authority to be talking about 9/11. At. All.”

Before Pelosi’s second statement on Sunday, the lack of a stronger response from the Democratic leadership in Congress — and no comment at all from Senate Minority Leader Chuck Schumer — had led Rep. Rashida Tlaib to accuse the party of using its Muslim congresspeople as props, without giving them adequate support against bad-faith attacks from Republicans.

Update: April 15, 7:00 a.m. ET
This story was updated to clarify the origins of the attack on Rep. Ilhan Omar and to add new statements released on Sunday from Omar and House Speaker Nancy Pelosi.