President Donald Trump's decision to cut $450 million in foreign aid to three Central American countries – collectively known as the Northern Triangle – will end dozens of projects designed to bolster security, the economy, education and judicial systems.

The goal of the programs is to improve conditions in the countries so citizens don't flee to the U.S. While Trump wants to cut the assistance, former officials say the programs are seeing results. For example:

In Honduras, U.S. Agency for International Development (USAID) officials have been working in local communities to reduce violence, contributing to a drop in the homicide rate every year between 2011 and 2018.

In El Salvador, where a struggling economy has pushed people to make the trek north, USAID helped small- and medium-sized businesses create more than 22,000 jobs between 2011 and 2016.

And in Guatemala, where the judicial system has been wrought with corruption and inefficiency, U.S. money has helped the government hire more judges and provided security for justice officials to protect them from cartels they are trying to prosecute.

Trump said the aid cuts, and his threat to close the southern border entirely, will punish governments of those countries for failing to prevent people from fleeing.

Where does the money go?

James Nealon, a former U.S. ambassador to Honduras, said Trump's explanation of foreign aid sounds as though "somebody tried to explain to him where the money goes and he just didn't get it."

Some U.S. money does go directly to government agencies, including grants to support police, border security agents and judicial employees in those countries. But Nealon, who resigned from the administration last year over policy disagreements, said most of the money goes to U.S. contractors, non-profit organizations, and other private groups under close supervision from USAID and the State Department.

Some supporters of Trump's immigration policies are also questioning the decision to cut off foreign aid to Central America.

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Mark Krikorian, executive director of the Center for Immigration Studies, which advocates for lower levels of legal and illegal immigration, said he doesn't understand why the president would punish the governments of El Salvador, Honduras and Guatemala when they cannot legally stop citizens from leaving.

Krikorian said he is skeptical that foreign aid cuts will change anything, and urged Trump to focus instead on pushing Congress to overhaul immigration laws to limit the ability of asylum-seekers to enter the United States.

"By focusing attention on Honduras and Guatemala and El Salvador, we're distracting attention from the real culprits: Nancy Pelosi and Chuck Schumer," Krikorian said, referring to the Democratic House speaker and Senate minority leader.

Violence, poverty, hunger

El Salvador, Honduras and Guatemala have struggled for years with violence, poverty and insecurity.

El Salvador was recently dubbed the murder capital of the world. In Honduras, citizens are still protesting the contested 2017 election. Guatemala's president has taken heat for trying to end a United Nations-backed anti-corruption commission that has successfully prosecuted corrupt officials.

All the while, the three countries are struggling with a historic drought that has put more than two million people at risk of food insecurity, according to the United Nations.

But a study published by Vanderbilt University said U.S. aid has helped improve conditions little by little.

The aid has paid for computer labs and job training for at-risk youths, grants for women entrepreneurs and programs to bring underground businesses into the legal economy. It has also funded community policing programs, the purchase of law enforcement equipment and training for police, judges and prosecutors.

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Researchers at Vanderbilt's Latin American Public Opinion Project surveyed 29,000 people living in five Central American countries, and found that those living in neighborhoods with U.S.-funded projects saw less violence. In those communities, 51% reported fewer murders and extortion attempts, 35% said they no longer avoided walking through dangerous areas and 25% said they saw a drop in drug sales.

"It's an extraordinarily rigorous study, and it's very persuasive," said Michael Clemens, a senior fellow at the Center for Global Development, who was not part of the report but has studied the reasons young people flee Central America for the United States.

Rising migration

Trump sees things differently.

The combination of violence, poverty and food insecurity in Central America has driven record numbers of families to head north to seek U.S. asylum.

On Tuesday, State Department spokesman Robert Palladino said rising migration showed that U.S. aid was not working.

Border Patrol agents apprehended more than 36,000 members of family units in February – a record – and border communities are being overwhelmed trying to care for them. That figure has steadily increased in recent months, with Border Patrol officials predicting a further rise for March.

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"The president has determined that these programs have not effectively prevented illegal immigration from coming to the United States, and they’ve not achieved the desired results," Palladino said. "It's not succeeded in stemming this flow."

Still, Clemens said cutting off funding was misguided. He said the evidence, including the Vanderbilt study, shows that U.S. aid has led to gradual progress in living conditions in Central America.

"There is literally zero evidence that bludgeoning the (Central American) governments and long-time partners of those governments is somehow going to produce security in the region," he said.