In 2015, after tens of thousands of unaccompanied immigrant children arrived at the U.S. border, the Obama Administration pledged seven hundred and fifty million dollars to the governments of Guatemala, Honduras, and El Salvador to fund security initiatives and development efforts. The aim was to decrease migration by improving conditions in the region. But its success was mixed—some local programs showed results, others less so, and migration has largely continued to increase—which has led to open questions about how best to proceed. Is more money the answer? Could the performance of certain programs be improved? Is the corruption of certain U.S. allies interfering with the broader initiative? In the context of the policy debate, though, there’s generally been consensus on one basic principle of cause and effect: if the U.S. government wants to stem the flow of people coming north from Central America, it has to try to address why they’re leaving in the first place. “If you’re making policy at the border,” Cecilia Muñoz, who headed the Domestic Policy Council in the Obama White House, recently told me, “you’re too late.”

On Friday, the President announced that he was ending all aid to Guatemala, El Salvador, and Honduras. “We’re not paying them anymore because they haven’t done a thing for us,” Trump said. By all accounts, the decision shocked officials at the Department of Homeland Security and the State Department—one, speaking to the Washington Post, described an atmosphere of “chaos.” A few days earlier, the Secretary of Homeland Security had met with representatives from the three Central American governments to pledge U.S. support. Arrests at the border are at the highest levels in a decade, and the number of families who are seeking asylum from Central America, Hondurans and Guatemalans in particular, has spiked. The President’s move, which will affect everything from development aid and humanitarian assistance to joint law-enforcement operations and anti-gang initiatives, will only make the crisis at the border worse. James Nealon, who was the Ambassador to Honduras under President Obama and later worked in D.H.S. during the Trump Administration, told me, “If he hates irregular migration now, he’s going to hate it a lot more once he cuts off aid, cuts the rug out from under friendly and coöperative governments, creates uncertainty and instability—and people really begin to move.”

Trump has threatened to cancel aid before, but this time the State Department has notified Congress of its plans, and the courts can’t readily intervene. “I’m not playing games,” Trump said over the weekend. To prove his seriousness, he’s also vowing to close ports of entry between the U.S. and Mexico, a move that would cost hundreds of millions of dollars in transborder commerce and upend the daily lives of millions of families, workers, and businesses on both sides of the border. Nealon said, “I believe that a lot of the rush to the border right now is directly attributable to the President’s rhetoric. During my time in Honduras, we saw the traffickers use the harsh border rhetoric to tell people, ‘the gringos are going to shut down the border, you have to go now.’ ”

At this point, rash action from the President hardly comes as a surprise. Last spring, in response to an uptick in the number of asylum seekers at the border, Trump publicly excoriated his D.H.S. Secretary, whom he blamed personally for regional migration patterns. In April, the Justice Department and D.H.S. formalized a “zero-tolerance” policy that gave rise to the separation of thousands of families seeking asylum. (A federal judge has since ordered the government to reunite them.) In the fall, as a large caravan of Central Americans travelled through Mexico to the U.S., the President issued a proclamation banning asylum altogether at the southern border, which a federal court promptly blocked. After these setbacks, the Trump Administration undertook a radical experiment on the south side of the border earlier this year. Under a policy called Remain in Mexico, which is currently being challenged in federal court, the U.S. is now forcing asylum seekers to wait indefinitely in Mexico while their claims move through backlogged American immigration courts. While the Mexican government was uncomfortable with the new policy, it agreed to it under pressure from the Trump Administration. Now the President is attacking Mexico anyway, for not doing more.

Over the weekend, I asked a State Department official whether members of the President’s cabinet supported the move to cut off aid to Central America; it was hard to imagine that anti-immigration hard-liners within the Administration would back a measure that will almost certainly lead to more migration. “The divide is mostly between political appointees and everyone else,” the official said. “ Pompeo, Mulvaney, Bolton, the leadership of P.R.M.”—the Bureau of Population, Refugees, and Migration, the division of the State Department in charge of refugee and migration policy—“all of them have supported this revamped foreign-assistance strategy.” The new mentality, the official explained, was that the U.S. should be “demanding a concrete ‘return’ on our investments.”

The Trump Administration has often undermined these investments itself, largely by thwarting the anti-corruption efforts it has helped fund with U.S. dollars. In December, 2017, the U.S. government recognized the election of an ally, President Juan Orlando Hernández, in Honduras, despite credible proof of wholesale fraud by his administration. Last year, the U.S. dealt a major blow to a landmark anti-corruption body, called the International Commission Against Impunity in Guatemala (CICIG), which was widely seen as a model of probity and effectiveness in the region. The commission was responsible for a corruption investigation that toppled the government of President Otto Pérez Molina and has provided training to Guatemalan law-enforcement agents. In January, the country’s current President, Jimmy Morales, whose family is under investigation for illicit campaign contributions, terminated the commission’s mandate, and, in September, barred the commission’s lead prosecutor, a Colombian, from entering the country. Not only did the U.S. refuse to support the CICIG against these attacks, but political appointees in the Trump Administration—including Nikki Haley, the former ambassador to the U.N., and Mike Pompeo, the Secretary of State—actively backed Morales and sidelined career diplomats who urged a different course. “The commission was so important because it helped reinforce the independent judiciary in Guatemala,” Claudia Escobar, a former appeals-court judge in Guatemala, told me recently. “With the CICIG in the country, judges knew they could do their jobs.” Without the promise of an independent judiciary, she added, “we have a rule-of-law problem.”

Migration patterns are hugely complex and multifaceted, driven by a range of overlapping factors that are extremely difficult to fully disentangle and quantify. But certain trends are well documented and understood—one of which, Adam Isacson, of the Washington Office on Latin America, told me, is that “there’s a direct link between unpunished corruption, on the one hand, and millions of people being unprotected and leaving the country, on the other.” The real question raised by the President’s decision to end aid to the region isn’t whether it will work—it won’t—but how badly it will fail to address the asylum crisis at the U.S. border. “There’s got to be the fundamental realization that this didn’t start yesterday, and that the [migrant] flow isn’t going to stop tomorrow,” Joy Olson, a human-rights advocate with extensive experience in the region, told me. “There aren’t easy fixes here. But the way you build solutions isn’t around the narrative this Administration wants to have.”