Chicago, Illinois - Father Brendan Curran knows many Chicago Catholics who supported Donald Trump's return to the presidency. But now they're watching immigration raids across their city in horror – and have Pope Leo XIV sharing their alarm.

"Almost to a person, they're in shock," Curran told AFP. "This isn't what they signed up for."

Trump's claim that Chicago is a virtual war zone, requiring him to deploy armed soldiers, is demonstrably false. But opposition to his hardline immigration crackdown is growing from a more peaceful source: the Catholic Church.

Pope Leo, who was born in Chicago and is the first American ever to head the global Church, has been outspoken in rejecting Trump's policies.

Politicians Gavin Newsom calls on House GOP to investigate "deeply offensive" leaked Young Republicans chats

Referring to the Church's opposition to abortion – something Trump's Republicans share with many Catholics – he cited the "inhuman treatment of migrants in the United States" and asked if that was "pro-life."

Chicago is the nation's third-largest city, where 30% of the population is Latino or Hispanic, many of them Catholic.

For Ariella Santoyo, a dress shop owner in the heavily Latino Little Village neighborhood west of Chicago, the reality of Trump's presidency versus the hope has been brutal.

Trump's conservative promises, especially on abortion, "appeal to a lot of people" in her community, she said.

But the immigration arrests – often conducted violently by masked, plainclothes men – were not what they wanted.

"We get that sense a lot from... friends that voted for Trump – family members that I know of that voted who said, 'Oh I never thought that this would happen.'"

Images of Immigration and Customs Enforcement (ICE) personnel chasing down migrants, bundling them into vans, and spraying protesters with tear gas play well to many of Trump's supporters.

He won the election last year in part on his apocalyptic, falsehood-filled rhetoric about violent migrants invading the US.

But in faith communities, and particularly among Catholics, there are increasingly visible rifts with the White House.

Donald Trump Trump shoots down Zelensky's request for Tomahawk missiles: "Putin wants to end the war"

"We as a church, and church leaders and faithful, have every right to say... our opinion on immigration policy in the United States. And right now we're in absolute opposition with the federal policy of the White House," Father Curran said.

In one symbolic act of defiance, pastor Gary Graf has started from outside Pope Leo's boyhood home on an 800-mile walk to New York's Statue of Liberty to protest Trump's policies.

And last weekend, hundreds of faithful joined a Eucharistic march from a Catholic church to the immigration authorities' facility in Broadview, west of Chicago, to try – unsuccessfully – to share communion with detained migrants.

"Our mission as a church is under threat," Curran, a Dominican friar, said. "When we are talking about feed the hungry, clothe the naked, shelter the homeless, and that is considered a federal crime, we're in trouble as a country."

Curran attended a recent prayer service outside Broadview's ICE facility. As a helicopter buzzed overhead, two dozen Catholics gathered to recite the rosary.

"We pray for President Trump" and other US officials "to continue opening their minds and hearts" to enacting compassionate immigration policies, one of them said.

Trump loyalists – including prominent Catholics Vice President JD Vance and White House Press Secretary Karoline Leavitt -- are defiant. And some of Trump's influential far-right supporters brand Leo a "woke" liberal.

"He is anti-Trump, anti-MAGA, pro-open Borders, and a total Marxist," influencer Laura Loomer, who has the president's ear, said on X.