PORTLAND, July 23 — Wearing bike helmets and yellow T-shirts, America’s mothers are confronting federal agents in combat gear to protect anti-racism protesters in Portland and, soon, other US cities where President Donald Trump has vowed to crack down.

Wall of Mums groups have formed in at least six cities including New York and Chicago in the four days since mainly white suburban mums in Portland started making human walls in front of demonstrators.

Carrying signs like "Feds stay clear. Mums are here,” and "I’m so disappointed in you — mum,” the Oregon women have been shoved and tear-gassed by agents. Some dads have joined too, bringing leaf blowers to blow away tear gas.

Images of federal agents wearing camouflage whisking away Portland demonstrators in unmarked vehicles last week mobilised the mothers. Protests against racial injustice have rocked the largely white city for nearly two months since the death of Black man George Floyd in Minneapolis police custody.

The deployment of federal agents in Portland last week is a flashpoint in a national debate over civil liberties and what demonstrators and local officials see as a political ploy by Trump, who is facing an uphill re-election battle.

"This was a call to action. I was honest, and I said that I didn’t know how to protest but I knew that something had to be done,” said Bev Barnum, a 35-year-old Portland mother of two who used Facebook to organise the group’s first demonstration of several dozen mums.

Carrying sunflowers, large peace symbol cut-outs and signs like "You need a time out,” hundreds of mothers now link arms on the frontline of nightly protests at the city’s federal courthouse, braving tear gas and other non-lethal munitions.

Trump threatened earlier this week to send FBI and other federal agents to several other cities to help local authorities crack down on a surge in violence in recent weeks. The programme, known as Operation Legend, began in Kansas City, Missouri.

‘We got gassed’

A "Wall of Mums” group in Washington called on mothers to gather at the "March Against Trump’s Police State” yesterday. Chicago organiser Katje Sabin said her group had been asked to attend a Saturday demonstration.

"If we have these groups of mums in yoga pants standing there, people kind of behave a little better,” Sabin, 57, said of police who she believes want peaceful protests but get "all excited and threatened and scared.”

Portland’s mothers thought officers from the Department of Homeland Security and other federal agencies would not use force against them at their first demonstration Sunday at the courthouse. They were wrong.

"We got gassed and that was the most heinous, excruciating experience in my entire life,” said Barnum.

The Wall of Mums movement carries on a tradition of maternal activism, notably the Mothers of the Plaza de Mayo in Buenos Aires who held weekly vigils for nearly three decades to draw attention to the disappearance of their children under a military dictatorship.

In Portland, Barnum and other organizers are trying to ensure their fame does not eclipse the anti-racism, anti-police brutality messages of protesters they are defending.

Barnum, who is Mexican American, coordinates with local Black protest leaders to support the wider movement.

Still, some activists such as E. Gomez have broken away from the mums, frustrated by what she calls "boomer-aged white women and men” who do not listen to concerns that they are drowning out the voices of people of colour.

"It’s quickly turning into a #wallofkarens. It’s feeling like a lot of optics and photo ops to make these white women feel better about themselves,” said Gomez, using a pejorative term to describe entitled, middle-aged white women.

Gomez, a woman of colour, plans to put on black clothing and return to the protests with another mother.

Luna Jane, 27, a black mother, is glad to have mums creating what she believes is a safer environment that has encouraged more protesters to come onto the streets.

"I’m fighting for my daughter’s rights to live in her own home safely,” said Jane, using an alias out of fear of doxing and referring to the Louisville police killing of African American emergency medic Breonna Taylor in her apartment.

"If I have to get hurt or even lose my life in that process, I will do so.” — Reuters