President Trump’s decision to launch his second term by declaring a national emergency at the U.S. border triggered an avalanche of opposition from Democratic governors, liberal members of Congress, and pro-migrant organizations vowing to challenge the constitutionality of his sweeping executive actions.

In Monday’s inaugural address, Trump pledged that “all illegal entry will immediately be halted.” The national emergency declaration includes provisions allowing for the deployment of additional military resources to finish the border wall, among other efforts.

“We will have the military at the southern border, but there are other elements of the United States government that will be working throughout the country,” an incoming White House official said during a Monday morning call with reporters.

The executive action targeting children of illegal immigrants, along with a raft of border-related orders Trump signed to overhaul U.S. immigration and border security, attracted condemnation from Pope Francis, as well a host of left-leaning groups.  

In an interview Sunday on Italian television, Francis labeled the mass deportation of illegal immigrants “a calamity,” remarks signaling a return to the friction between the pontiff and Trump that marked the president’s first term in the White House.

“This, if it’s true, will be a disgrace, because it will make poor unfortunates who have nothing foot the bill for [global] imbalances,” the pope said. “That doesn’t work. You don’t solve things that way. You just don’t.”

Francis, who has made illegal immigrant and refugee rights a top priority of his papacy, is the most prominent voice pushing back against Trump’s sweeping changes to U.S. immigration policy to implement mass deportations.

Other self-anointed U.S. leaders of the Trump resistance also denounced the stricter immigration policies and pledged not to follow the new federal birthright law while fighting it in court.

“That’s unconstitutional. We will not follow an unconstitutional order,” Illinois Gov. JB Pritzker, who is eyeing a 2028 presidential run, told reporters Monday. Pritzker blasted Trump’s deportation plans, which reportedly could begin in cities across the country, including Chicago, as early as Tuesday.

“They have not communicated with us. I’m reading the same things you are,” Pritzker continued. “This is indicative of what you’re going to see of the Trump administration for the next four years. It’s chaos.”

Refugees International, a nonprofit advocacy organization, deemed Trump’s first moves to tighten immigration laws “extreme” and “an attempt to reverse America’s proud legacy and tradition of providing refuge to people forced to flee their homes.”

“Make no mistake, these orders are not just about stopping irregular migration – they also target long-standing legal migration pathways in ways that will endanger vulnerable people, undermine border security, and harm the U.S. economy,” the group said in a statement.

California Gov. Gavin Newsom, another presumed 2028 presidential contender, declared himself the leader of the Trump resistance just days after the president’s victory. On Monday, however, he was far more restrained. After weeks of searing criticism over state and local officials’ response to the Los Angeles wildfires, Newsom is walking a careful line with federal disaster aid on the line and with Trump set to visit the state on Friday.

Newsom, in a post on X.com, stressed the need to find “common ground” and efforts to reach “shared goals.”

“Where our shared principles are aligned, my administration stands ready to work with the Trump-Vance administration to deliver solutions and serve the nearly 40 million Californians we jointly represent,” he wrote.

Undeterred by the angry opposition, Tom Homan, Trump’s incoming “border czar,” Monday defended Trump’s crackdown. Homan estimated that more than 10 million illegal immigrants have flooded into the country during the Biden administration and argued that Biden and outgoing U.S. officials have “blood on their hands” for the death of 22-year-old nursing student Laken Riley and other U.S. citizens slain by immigrants living in the U.S. illegally.

Deportation raids targeting criminals will begin in major cities across the country Tuesday, Homan said, although he noted that the administration is reconsidering details of a planned Chicago ICE raid after a leak to the press about the operation occurred.

Earlier in the day, the Senate passed the Laken Riley Act on a bipartisan vote, with 12 Democrats joining Republicans to vote for the bill mandating the detention of more illegal immigrants charged with crimes. The measure now heads to the House, which passed a similar bill last month.

Gallego co-sponsored the Laken Riley bill but opposes ending birthright citizenship, another idea broached during the campaign and pressed by Trump on his first day in office.

“We need to address our broken immigration system and secure the border,” Gallego wrote on X.com, “But executive actions like this run contrary to the ideals of what makes our country great, and I will do all I can to fight this anti-American executive order.”

The battles lines over Trump’s expected revocation of birthright citizenship came into focus months ago. The immigration executive actions are a combination of campaign promises and policy ideas from the first term that never materialized.

Late Monday night, just hours after Trump signed the executive order ending birthright citizenship, the American Civil Liberties Union and several other immigration rights groups sued, accusing the administration of flouting the Constitution, congressional intent and longstanding Supreme Court precedent.

“Denying citizenship to U.S. born children is not only unconstitutional – it’s also a reckless and ruthless repudiation of American values,” Anthony Romero, executive director of the ACLU, said in a statement. “Birthright citizenship is part of what makes the United States the strong and dynamic nation that it is. This order seeks to repeat one of the gravest errors in American history, by creating a permanent subclass of people born in the U.S. who are denied full rights as Americans.”

The ACLU and the other groups are suing on the basis that ending the citizenship of children born to illegal immigrations violates the Fourteenth Amendment, which states that “all persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States.”

“We will not let this attack on newborns and future generations of Americans go unchallenged,” Romero added. “The Trump administration’s overreach is so egregious that we are confident we will ultimately prevail.”

The incoming administration on Monday also shut down CBP One, an app that helped illegal immigrants and asylum seekers enter the United States.

House Homeland Security Committee chairman Mark Green applauded the flurry of immigration restrictions Trump imposed on his first day in office, deeming them a “restoration of American sovereignty at our borders.”

“We’re going to take the handcuffs [off ICE] that were placed on them by the Biden administration, and we’re going to put them on the bad guys,” Homan added during an appearance on Fox News Monday night.