Central American families were crossing the border in growing numbers when Secretary of State Antony Blinken announced Feb. 6 via tweet that the Biden administration would cancel a series of Trump-era agreements with El Salvador, Guatemala and Honduras to restrict asylum.

Biden supporters cheered the move as another campaign promise fulfilled, but in headlines across Central America, where deepening economic hardship has many considering a trip north, the announcement appeared to confirm the new sales pitch of smuggling guides: Donald Trump and his cruel policies are gone, and the United States is easing border controls.

Biden administration officials have tried to counter that message by urging migrants not to attempt the journey. The next several weeks will be a crucial test, as Biden’s team transitions from campaigning on immigration to managing a dysfunctional U.S. immigration system and border pressures closely attuned to changes in national policy.

At the center of that challenge is Biden’s pledge to make the immigration system more humane and orderly without triggering a border rush that could bring chaos, unsafe conditions and a GOP backlash. The Biden team’s strategy has been two-track: promoting the rollback of Trump’s policies to the president’s core supporters while urging migrants to stay away.

“These actions do not mean that the U.S. border is open,” Blinken said in a statement after canceling Trump’s asylum agreements. “While we are committed to expanding legal pathways for protection and opportunity here and in the region, the United States is a country with borders and laws that must be enforced.”

An incomplete section of a border wall stands near Brownsville, Tex, on Feb. 9. Construction on the border wall was halted on President Biden’s first day.

Alan Bersin, who was commissioner of U.S. Customs and Border Protection (CPB) during President Barack Obama’s first term, said these kinds of “mixed messages” are difficult to pull off. “People will hear what they want to hear,” he said.

“A welcoming message that says ‘Don’t come now’ likely will have no deterrent effect on the smuggling networks and push factors in Central America that have become dramatically worse,” Bersin said. “There is an understandable desire to reverse many cruel and punitive measures of the Trump years, but you need to do it in a way that does not overwhelm the border.”

In his first month as president, Biden has issued a flurry of immigration-related orders to halt Trump’s border wall, end the “Remain in Mexico” program for asylum seekers, curb deportations and welcome far more refugees. His administration sent Congress its plan this week to offer a path to citizenship for millions of immigrants who lack legal status, part of an ambitious overhaul whose chance of winning a filibuster-proof majority appears slim.

Managing the border is a more immediate challenge. U.S. agents have made more than 70,000 arrests and detentions each of the past four months, the busiest span for that period in at least a decade. Central America’s fragile economies have been hammered by the coronavirus pandemic and powerful hurricanes, pushing more to flee.

Biden’s team includes Homeland Security Secretary Alejandro Mayorkas, White House policy adviser Esther Olavarria and national security adviser Roberta Jacobson, a former U.S. ambassador to Mexico — all immigration policy veterans who have managed previous crises at the border. They are well-versed in the migration patterns that have vexed previous administrations of both parties whenever large numbers of Central American families and children arrive seeking asylum or humanitarian protection.

With a U.S. court backlog of hundreds of thousands of cases, and limits on the government’s ability to detain and rapidly deport those groups, they are often released into the United States while their asylum claims are adjudicated, a process that can stretch years.

Border hard-liners deplore this model as “catch-and-release,” while immigrant advocates say families fleeing violence have a legal right to make a claim and receive due process.

The latest Department of Homeland Security figures show that 28 percent of the 1.7 million Guatemalans, Hondurans and Salvadorans taken into custody along the border between 2014 and 2019 have been sent back to their home countries, even though just 7.6 percent qualified for humanitarian protection or some other form of legal residency.

The vast majority, or 64 percent, of the 1.7 million still have unresolved court claims or have remained in the United States despite being ordered to leave, DHS statistics show.

Many of the immigrant advocacy groups that Trump shut out have widely applauded Biden’s initial moves, with some urging bolder steps to curb detention and deportation.

Frank Sharry, the founder of the immigrant advocacy group America’s Voice, said Biden has “leaned in” on immigration, in contrast to the more cautious early days of Obama’s first term. He pointed to recent polling that shows broad bipartisan support for programs such as Deferred Action for Childhood Arrivals that were once considered controversial as a sign that the center has shifted, affording more latitude to a Democratic president.

“Trump forced a referendum on whether we should be a welcoming nation to refugees and immigrants,” Sharry said. “He and [policy adviser] Stephen Miller thought demonization and harsh policies would win over the persuadable middle, and it backfired.”

Sharry acknowledged that it will take time to reverse Trump’s measures, and said he’s encouraged by the staff hires and steps Biden has been taking. “That provides a lot of goodwill,” he said.

Other activists see more urgency.

“We are impatient because we see the necessity on the ground,” said Erika Andiola of the Texas-based Refugee and Immigrant Center for Education and Legal Services, which provides legal aid to asylum seekers.

Migrants await processing after being apprehended at the U.S. border near Mission, Tex., on Feb. 10.

Andiola is among those who want Biden to push Democrats in Congress to use the budget reconciliation procedure to pass an immigration bill with a simple majority, and to maximize executive authority in the meantime.

“We can’t wait for Congress to do something and have so many people being deported, arrested and detained,” she said. “They need to act quicker and use every single tool at their disposal to create these changes.”

To limit illegal border crossings, the Biden administration has relied mostly on a Trump-era emergency health order, known as Title 42, that since March has allowed U.S. agents to rapidly “expel” about 400,000 migrants back to Mexico in an effort to prevent the spread of the coronavirus. But a change in Mexican law that took effect last month prompted authorities there to stop taking back as many families.

Biden has ordered a review of Title 42, which remains in place. Last month, the number of families and children taken into custody along the Mexico border rose sharply, to more than 13,000, but it remains far below the record influx in 2018 and 2019, when more than 88,000 parents with children crossed the border in May 2019 at the peak of the crisis. It was that surge that prompted Trump to threaten Mexico with tariffs, and its government responded with an unprecedented crackdown.

Trump officials also made deals with El Salvador, Guatemala and Honduras to permit U.S. authorities to send asylum seekers to their countries instead of allowing them to seek protection in the United States. Those were the agreements Blinken said the Biden administration will terminate.

Trump also pressured Mexico to accept more Central Americans as part of the “Remain in Mexico” program, or Migrant Protection Protocols, that the Biden administration is also ending.

The Biden administration has started to allow an estimated 25,000 migrants with active MPP cases to begin entering the United States through a phased intake process. A priority will go to the most vulnerable, including some of the families living in a tent camp along the banks of the Rio Grande amid dangerously low temperatures.

Mayorkas told NPR last week that the Biden administration is moving as fast as possible to improve conditions for asylum seekers stranded by Trump policies.

“I cannot overstate the fact that the prior administration completely dismantled the program and it takes time to rebuild it in a way that addresses the humanitarian needs of the individuals who seek to access it,” Mayorkas said. “And if people wait and they see how this works in an orderly, safe and efficient manner, that is the best ticket to greater success in the future.”

He followed with a warning: “If, in fact, they don't wait, we will see the detriments of that failure to wait, and that, regrettably, will be an important lesson with respect to what we have cautioned.”

White House officials have been more adamant, saying migrants who come now will be returned to Mexico, not released.

U.S. Customs and Border Patrol agents stand on the international bridge near a migrant camp in Matamoros, Mexico, on Feb. 9.

But that’s not precisely what’s happening. Many families, especially those that arrive at the border with children younger than 7, are being detained and then quickly released into the United States, mostly in the Rio Grande Valley of South Texas.

The releases have raised fears of a coronavirus resurgence in one of the areas hit hardest by the pandemic. CBP does not administer coronavirus tests unless migrants display symptoms of illness, but the state has sent thousands of testing kits to nonprofit groups and local authorities to improve screening.

“As someone living on the border during a pandemic, I’m very concerned we’re sending a wrong message to migrant caravans that they’re welcome,” said Rep. Vicente Gonzalez (D-Tex.), whose district runs south from San Antonio to the Rio Grande Valley.

The pandemic has restricted travel for the Mexican nationals whose spending at stores on the U.S. side is a bedrock of the border economy, Gonzalez noted. “Our hotels are empty, our malls are empty, so how would it make sense to send a message to migrants and caravans that if they make it to the southern border they will be released into our communities?”

Democrats in Texas’s Rio Grande Valley are also wary of losing more ground to Republicans in the majority-Latino areas where Trump made substantial gains in November, especially along the Mexico border.

“We can’t run away as Democrats from reality,” Gonzalez said. “We’re not going to separate families or cage kids, but we need to continue having smart, good policy on our border to deal with asylum claims.”

Andrew Selee, the president of the nonpartisan Migration Policy Institute, said it’s too soon to tell whether the growing number of families arriving will snowball.

“Migration is sensitive to messaging, but more sensitive to policy change,” Selee said. “There’s probably not going to be a massive surge until people have a real chance of getting in.”

He added: “Once people have a real chance, they will come in larger numbers.”

A group of undocumented immigrants walk toward a Customs and Border Patrol station after being apprehended at the U.S. border near Mission, Tex., on Feb. 10.