Feminists are fighting this week after the Women's March announced Sen. Bernie Sanders, I-Vt., is slated to deliver the opening speech at their upcoming convention.

Sanders is set to address the group's Women's Convention, a three-day event hosted in Detroit, on Oct. 27.

"We believe as women ... that we ought to have more than just women at the Women's Convention," Women's March co-founder Tamkia Mallory told the Detroit Free Press. "People want to hear from the leadership from within our government who can give us some insight about what's happening ... so we can know what we need to do to be able to organize."

Influential feminist leaders and organizations were not convinced.

"Incredibly disappointed @womensmarch.You couldn't find any inspiring, powerful, woman to give the opening speech? I can give u a long list," tweeted Will & Grace actress Debra Messing.

"Pretty amazing. How did the WomensMarch not find any woman for this gig? Unfollowing," Center for American Progress President Neera Tanden said.

MSNBC host Joy Reid responded to the news by asking, "So... there were no women available ... to open the womens convention...?"

Alex Griswold of the Washington Free Beacon has a good roundup of the reactions here.

Ostensibly frustrated by confusion on social media, Mallory clarified later on Thursday, "MAXINE WATERS IS THE #WOMENSCONVENTION HEADLINER! Y'all may not have noticed but we announced that weeks ago." While Sanders will be the convention's first speaker, Rep. Maxine Waters, D-Calif., has the distinction of being its headliner.

Since its demonstrations the day after President Trump's inauguration, the Women's March has enjoyed broad support from feminists, engaging some of the movement's most extreme figures in subsequent activities. Though its post-inauguration rallies somehow managed to find appeal with women outside progressive circles, the organization has since proved its leadership is primarily interested in representing the values of radical progressives.

Reflexive expressions of outrage and disappointment over the group's decision to give Sanders the opening platform are another reminder of why tensions are running high in the Democratic Party right now. Some of the upset over Sanders' speech is certainly rooted in lingering resentments held by staunch supporters of Hillary Clinton. Some of it also shows how pressures from progressives increasingly bent on demanding nothing short of purity (like the Women's March itself) easily inflame intra-movement conflict.

As of Thursday evening, the Women's March has not reversed its decision to have Sanders open the conference.

Emily Jashinsky is a commentary writer for the Washington Examiner.