Over the weekend, President Donald Trump posted a series of racist tweets attacking Democratic women of color in Congress: likely the progressive “squad” of Reps. Alexandria Ocasio-Cortez, Ilhan Omar, Rashida Tlaib and Ayanna Pressley (though he didn’t name any of them explicitly). In the tweets, Trump suggested they “go back” to “the crime-infested places from which they came.” All four women are American citizens, and three of the four were born in the United States (Omar was born in Somalia, and became a US citizen in 2000).

But Trump’s attacks on these four first-term lawmakers are just the latest in a long pattern. Since they joined Congress, these women have faced frequent backlash and scrutiny, seemingly almost every time they speak out publicly, both from Republicans and from within their own party.

Omar, for example, has received death threats, faced calls to resign from the president, and been censured by her own party over various controversial statements she’s made about Israel.

This time, Democrats were unequivocal in their condemnation of the attack on the four progressive women of color. House Speaker Nancy Pelosi quickly responded in their defense on Sunday, tweeting that “our diversity is our strength and our unity is our power” and introduced a resolution to the House on Monday condemning Trump’s tweets. But just last week, Pelosi was criticizing them for being too outspoken on social media, telling the New York Times: “All these people have their public whatever and their Twitter world. But they didn’t have any following. They’re four people and that’s how many votes they got.”

That public feuding in the caucus (which continued over the weekend) seems to have provoked Trump’s tweetstorm.

From the beginning, there has been something distinctly racial (and gendered) about the aggression directed by various parties at Omar, Ocasio-Cortez, Tlaib, and Pressley. Omar is black and one of the first Muslim women in Congress. Ocasio-Cortez is Latina. Pressley is black. And Tlaib is the daughter of Palestinian immigrants.

All four have been surrounded by controversy and personal attacks since they took office in January — attacks that are explicitly about silencing outspoken women of color.

Congress has a problem with how it’s responding to more women of color in its mix

Rep. Omar first became the subject of scrutiny for criticizing the influence of the American Israel Public Affairs Committee (AIPAC), a pro-Israel lobbying group, by making comments that many perceived as invoking anti-Semitic tropes.

Though Omar apologized, she has continued to face censure not just from Republicans but also from her own party: House Democrats voted on a resolution condemning hate speech that was widely seen as a reprimand to Omar. And she has become a frequent target for Trump, who has repeatedly smeared her and even called for her to resign.

And Omar is far from the only woman new to Congress who has been a lightning rod for controversy and personal attacks:

Rep. Alexandria Ocasio-Cortez has become a new favorite target of conservative media, which has criticized everything from her policies to her tweets, her clothes, her bank account, and her working-class upbringing.

Rep. Rashida Tlaib sparked controversy when she made a comment about racism during the Michael Cohen hearings that ignited a gross overreaction and outrage from Republican Rep. Mark Meadows, who asked for Tlaib’s comments to be stricken from the record — yet another form of silencing.

Ocasio-Cortez, Omar, and Tlaib have a few things in common: They are all young, progressive women of color who took office this winter and immediately challenged conventional Washington thinking on foreign policy, climate change, economics, and more. They’ve all faced considerable backlash from Republicans and from their own party. And they have all been met with a very specific reprimand: Be quiet.

This isn’t something new to women of color: Studies have shown that women of color in the workplace are routinely marginalized, stereotyped, excluded, and silenced — a trend that’s only exacerbated in Congress’s overwhelmingly white and male halls.

That’s why the attacks feel all too familiar to many women of color; they’re part of a long, established pattern of attempts to silence those who step out of the roles society has ascribed to them.

The stances Omar, Tlaib, and Ocasio-Cortez have taken are certainly worth debating on ideological grounds. And were they white men making the same comments, perhaps they would be. But that’s not always what’s happening.

Instead, these three outspoken women have become the public faces of the shift toward a more diverse Congress and have become a locus for the same patterns of biased behavior that researchers and experts have found women of color in leadership often encounter.

As a result, they have been met with aggressive and extensive calls to shut up and go away.

Studies show women of color in Congress have long been marginalized, excluded, and silenced

Omar, Tlaib, and Ocasio-Cortez have been in office for just over three months. In that incredibly short span of time, they’ve faced repeated attacks at every turn. They’ve been the subject of whispery, catty, anonymously sourced stories about how other members of Congress want to “rein them in” or “wrangle” them. Politico reported earlier this spring on how House Speaker Nancy Pelosi is “wrangling” first-term members like these three women.

Pelosi told Politico: “You don’t want to be condescending, but you also have to be courageous enough to say, ‘This is how we’re going to do this,’ in the right way.”

In a July interview, Pelosi doubled down on that message, telling the New York Times: “All these people have their public whatever and their Twitter world. But they didn’t have any following. They’re four people and that’s how many votes they got” in Congress after the four liberal women were the only Democrats to vote against a border funding bill that moderate Democrats supported.

In a meeting of the House Democratic caucus in early July, Pelosi also told Democrats: “You got a complaint? You come and talk to me about it. But do not tweet about our members and expect us to think that that is just OK.” Ocasio-Cortez responded that this was “explicit singling out of newly elected women of color.”

These women are politically progressive, and this has led to policy clashes with more moderate Democrats. Any new member introducing ideas outside their party’s mainstream might face some public backlash, of course. But would they have faced the same level scrutiny if they were white men? Probably not.

We know that because this is not a new phenomenon: Political scientist Mary Hawkesworth found in a 2003 study that women of color in Congress were routinely silenced, stereotyped, and excluded, and often had their authority challenged.

Hawkesworth analyzed interview transcripts from 81 women in the 103rd and 104th Congresses, using a piece of welfare reform legislation that made its way through the legislature as a case study. She found a pattern of “silencing, excluding, marginalizing, segregating, discrediting, dismissing, discounting, insulting, stereotyping, and patronizing” women of color by white members of Congress, and that these tactics were frequently used “to fix women of color ‘in their place.’”

This isn’t unique to Congress, either. A 2015 study of women of color in STEM (science, technology, engineering, and math) fields found that 50 percent of the women surveyed reported experiencing backlash for behaviors that were viewed as stereotypically male, such as assertiveness or expressing anger. A third of the women of color in the study said they were met with adverse reactions when they promoted themselves.

Having studied these behaviors, Hawkesworth sees the backlash against Omar, Ocasio-Cortez, and Tlaib as merely a continuation of a longstanding pattern of silencing women of color.

“Much of the uproar about the ideas of Alexandria Ocasio-Cortez (the Green New Deal) or Ilhan Omar (the power of special interests) replicates long-standing racializing tactics to undermine their authority and silence their voices, to paint them as ‘radicals’ and out of touch with the ‘real America,’” Hawkesworth told Vox over email.

“Whether casting Alexandria Ocasio-Cortez as a ‘socialist’ with totalitarian tendencies or Ilhan Omar as a ‘terrorist,’ their words are being twisted to suggest that they pose a threat to our nation — when they seek to promote more meaningful democratic practices,” she added.

Even when women of color aren’t explicitly being told to pipe down, stereotypes help subconsciously keep their voices from being heard when it matters most.

“Many people in our society are used to only seeing women of color in subservient positions, and think of them in stereotypical ways: as housekeepers, domestic workers, babysitters, service workers,” Soraya Chemaly, a feminist writer and author of Rage Becomes Her: The Power of Women’s Anger, told Vox. “Studies show how often it is that women of color and black women are mistaken for janitorial staff in their own offices, for example.”

She’s right: The same 2015 study mentioned above also found that African American and Latina scientists were routinely mistaken for janitors in their own workplaces. Culturally, many people subconsciously still envision leaders as white and male, even if they don’t realize it.

This type of implicit bias affects women of color every day. Chemaly said she has experienced this herself: While at a ceremony to receive an award recently, she said, “a group of men, writers and editors, walked over and asked me where I was going to whisk them off to next,” implying that they thought she was an event staff member, rather than a nominee for an award.

“It just didn’t seem to occur to the man who asked the question that I could be there as a peer — and certainly not as a nominee for an award,” she added. “That sort of thing happens to women of color all the time.”

Even Ocasio-Cortez has said that in her first weeks on Capitol Hill, she was routinely mistaken for a staffer, intern, or spouse rather than a Congress member.

It’s no coincidence that Omar, Tlaib, and Ocasio-Cortez have been three of the most scrutinized, most frequently attacked new members of Congress. America is still not used to seeing women who look like them holding some of the nation’s highest offices.

The hypocrisy of the backlash against Ilhan Omar

The series of controversies around Omar also epitomize a particular challenge that black women face: the risk of being perceived as an “angry black woman,” all for daring to take a critical stance and standing by it.

Omar came under fire first for a tweet that was perceived as invoking negative stereotypes about Jews and money. Several weeks later at an event, she tried to clarify her earlier remarks, saying that she wanted to talk about the United States’ relationship with Israel and the role the pro-Israeli lobby group AIPAC plays in that relationship — not Jewish people.

For her comments about Israel and AIPAC, she’s been widely criticized by her fellow members of Congress, who have called her remarks anti-Semitic, and by President Trump, who called for her to resign.

Would there have been so much outrage from Congress if a white man had said the same things? Unlikely. Republicans, including Trump himself, have a much worse problem with anti-Semitism. As Vox’s Zack Beauchamp wrote earlier this year:

Congress has conveniently ignored anti-Semitic remarks when they have come from white, male, Republican politicians like Kevin McCarthy and Trump. But when a similar — though much less offensive — comment came from a black Muslim woman, both parties pounced.

It wasn’t just Republicans; after she made her comments about AIPAC, House Democrats introduced a resolution condemning anti-Semitism that was widely seen as a rebuke to Omar. The resolution was later broadened to include Islamophobia and white supremacy as well, after members of the Congressional Black and Progressive caucuses pushed back on the resolution, asking why Congress was punishing Omar in the age of Trump.

Omar’s case is, sadly, not unique: She is just the latest example of outspoken black women in Congress being scolded and silenced. Last summer, Rep. Maxine Waters (D-CA) was widely admonished, even by the leaders of her own party, when she suggested that activists who see a Trump administration official in a restaurant or public place should confront them.

And Sen. Kamala Harris (D-CA), who is now running for the Democratic nomination for president, has been repeatedly interrupted and talked over by her male colleagues in the Senate.

Alexandria Ocasio-Cortez has been chastised by her own party for being too vocal

Ocasio-Cortez, a rising progressive star, quickly gained notoriety in part due to her active use of social media. Unlike many members of Congress who use social media accounts to post relatively staid, publicist-approved updates about their comings and goings, Ocasio-Cortez uses the platform to respond to critics and comment on news.

In response, several Democratic members of Congress told Politico that they were afraid she would “mean-tweet” them and wanted to “rein in” her Twitter usage. One anonymous House Democrat said to Politico, “She needs to decide: Does she want to be an effective legislator or just continue being a Twitter star? There’s a difference between being an activist and a lawmaker in Congress.”

Ocasio-Cortez also recently shared a live stream on Instagram while she answered questions from followers, drank wine, and assembled an Ikea desk. Many of her millennial women supporters found the live stream relatable and authentic — but the Federalist called it a “bizarre display,” while Fox News host Tucker Carlson mocked her on his show, saying: “The AOC moment will pass. It’s too stupid to continue.”

But though Ocasio-Cortez is notably prolific on Twitter, she isn’t the only lawmaker who expresses their personality online.

Several men in Washington — from Sens. Chuck Grassley (R-IA) and Cory Booker (D-NJ) to the late John Dingell and, of course, Trump — are prolific, candid, and unpredictable on Twitter. With the exception of Trump, whose tweets are known to regularly send his staff scrambling, none of these men has been publicly chastised for his social media usage the way Ocasio-Cortez has.

When male politicians are vocal on social media, they’re praised for their authenticity. When women do the same, they’re mean girls who need to be reined in.

“I think responses to [Ocasio-Cortez] have a lot to do with the fact that she’s young, charismatic, the digital native, a woman of color, and gives the appearance of following her own rules,” says Chemaly. “In our culture, we don’t give a lot of credence yet to what girls and young women say and do, anywhere. I think she causes a certain amount of cognitive dissonance in her own party because of it.”

Rep. Rashida Tlaib was criticized for pointing out racism

Tlaib, a Detroit native who has proudly displayed her Palestinian heritage, immediately became the subject of controversy when she was sworn into her first term as a Congress member in January. A video emerged of her saying, of Trump, “We’re gonna impeach the motherfucker!”

Many of her fellow Democrats were clutching their pearls over her word choice; Rep. Jerry Nadler (D-NY), chair of the House Judiciary Committee, told CNN: “I don’t really like that kind of language.”

Tlaib later faced backlash again when ex-Trump lawyer Michael Cohen testified before the House Oversight Committee, of which Tlaib is a member. Cohen, in his testimony, accused Trump of being racist; Republican Rep. Mark Meadows objected to this characterization and argued that Trump had hired Lynne Patton, a black woman, to work for him at the Trump Organization, and therefore Trump could not be racist.

When it was Tlaib’s turn to question Cohen, she responded to Meadows:

Just because someone has a person of color — a black person — working for them does not mean they aren’t racist. And it is insensitive that some would even say — the fact that someone would actually use a prop — a black woman — in this chamber, in this committee is alone, racist in itself.

Meadows was immediately outraged: He called for the comment to be stricken from the record and then launched into a rant about how offended he was that Tlaib had suggested he was racist, going so far as to talk about his black relatives and friends as evidence to rebut the claim (again, invoking the misguided idea that simply knowing a person of color means one cannot be racist).

Their exchange became about Meadows and his hurt feelings, and Tlaib had to reassure him repeatedly that she was not calling him personally racist, but rather noting that the action was racist.

The entire incident ended up distracting from Tlaib’s original message about the subtle ways racism was being propagated in America’s legislature — a point that only a Palestinian woman and one other woman before her had thought to raise.

We still have a long way to go in how America treats women of color in politics

As noted, numerous studies have shown that women of color are used to being treated like outsiders who haven’t earned their spot; to having their authority and their credentials questioned, scrutinized, and even disregarded; and to being told to be quiet and wait their turn.

That goes double in historically white, male institutions like Congress, where women of color have successfully fought their way in the door only in the past few decades: The first woman of color elected to Congress was Patsy Mink of Hawaii, an Asian American who was elected in 1964, followed by Shirley Chisholm, a black woman, in 1968.

Despite the fact that this year’s new Congress was the most diverse class in history, not much has changed: Currently, 78 percent of lawmakers are white; 76 percent are male. And of the 127 women serving in Congress, just 47 are women of color — out of a total of 535 combined members in the House and Senate.

At least on a subconscious level, many women of color are still seen as relative outsiders in the white, male world of Congress.

Whether or not you agree with Omar, Tlaib, and Ocasio-Cortez’s opinions ideologically, they deserve to have a voice in the public debate. They are members of Congress who are pushing the boundaries of dialogue around public policy and offering new perspectives and new ideas, yet they face an inordinate amount of pressure to stay in line, keep their heads down, and be quiet.

A woman of color who owns her power, who disagrees with the party line, who maybe even dares to get angry, is still perceived as a threat to the white men who have traditionally controlled most of the power in Washington. This Congress might look more diverse, but there is still a long way to go before it sounds that way.