House Democrats who are women plan to wear white to Donald Trump’s first address to Congress Tuesday night, a throwback to outfits suffragettes once wore to protests. The Democratic Women’s Working Group, led by chair Rep. Lois Frankel of Florida, announced in a statement that its matchy-matchy plans were “a reminder to continue the ongoing fight to attain equal rights for all women.”

“We wear white to unite against any attempts by the Trump administration to roll back the incredible progress women have made in the last century, and we will continue to support the advancement of all women,” Frankel said in the statement. “We will not go back.”

It might seem an odd choice to wear a color worn by first-wave feminists—not to mention a color that stains easily and gets paired with “nationalism” far too often in the current administration—to represent a commitment to moving forward, not back. But white, for better or worse, has become the go-to color of mainstream liberals protesting misogyny and celebrating women in politics. On the night she accepted the Democratic Party’s presidential nomination, Hillary Clinton wore an all-white getup. Ditto when she became the party’s presumptive nominee and when she debated Donald Trump for the third time. Women embraced this suffragette theme on the day of the election, tweeting photos of their white outfits with the hashtag #wearwhitetovote in celebration of the people who fought to get them the franchise. The white jacket Clinton wore on Inauguration Day was read by many as one final nod to the history that would have to wait to be made.

Frankel told Fortune that the women are protesting with the color of their blazers because they wanted to be “respectful and dignified.” “We’re not going to wave signs,” she said. There are 66 female Democrats in the House, and judging by a photo Rep. Nancy Pelosi tweeted Tuesday afternoon, at least 40 women are participating. Pelosi is wearing a purple shirt under her white jacket; purple represented loyalty among suffragettes.

Tonight, our Democratic #WomenWearWhite in support of women's rights -- in spite of a @POTUS who doesn't! pic.twitter.com/kKJpfV5iUE — Nancy Pelosi (@SpeakerPelosi) February 28, 2017

The working group said in its statement that Democrats wearing white are showing support for Planned Parenthood, affordable health care, reproductive rights, equal pay, paid leave, affordable child care, and “lives free from fear and violence.” Rep. Barbara Lee of California posted on Facebook that she is wearing white “in honor of the generations of women who marched and fought for our sacred rights.” “President Trump needs to know that his sexist, chauvinistic, and predatory behavior is unacceptable and un-American,” she wrote. “Our rights—and our bodies—are not up for grabs.”

Trump has proven easily distracted by insults, offended by protests against him, and disturbed by women who mock him. This could make the white-out an effective strategy for disarming the president during his big speech. Basketball fans often stand behind the basket where the opposing team is trying to score and wave their hands during free throws. Likewise, 40 or more women (and men?) wearing white might rattle Trump’s nerves and throw him off his already-wobbly game.