Five former commanders of U.S. Southern Command have warned in an open letter that cutting aid to Central America will only make matters worse on America's southern border.

“As former Commanders of U.S. Southern Command, we have seen firsthand that the challenges in the region cannot be solved by the military alone but require strengthening investments in development and diplomacy,” the commanders wrote, in a letter released Monday by the U.S. Global Leadership Coalition.

It was signed by Army Gen. Barry McCaffrey (Ret.), commander from 1994 to 1996; Marine Gen. Charles Wilhelm (Ret.), commander from 1997 to 2000; Army Gen. James Hill (Ret.), commander from 2002 to 2004, Army Gen. Bantz Craddock (Ret.), commander from 2004 to 2006, and Navy Adm. James Stavridis (Ret.), commander from 2006 to 2009.

The letter comes in response to the State Department's recent announcement that it would end hundreds of millions of dollars in foreign assistance to El Salvador, Guatemala, and Honduras — countries where many migrants have fled violence or poverty and headed north to seek asylum.

The State Department had requested about $183 million in aid for those three countries in 2019, mainly focused on economic development, governance, and education. Assistance in the region addresses a variety of challenges, a June 2018 State Department release said, such as “security, governance, and economic drivers of illegal immigration and illicit trafficking.”

For example, according to State, foreign aid to this “Northern Triangle” contributed to $92.2 million in exports and created over 29,000 jobs in Central America in 2017. The release also touted U.S. support that led to reductions in violence and arrests of gang members.

“We know that if we invest at the scale of the problem, it works because we've seen it work in Colombia, where a sustained comprehensive civilian-military effort helped Colombians end the longest conflict in the Western Hemisphere and transform their country into a key security and trading partner,” the letter from the former commanders said.

On the flip side, the U.S. spent $18.9 billion on border security and immigration enforcement in 2017, according to a White House fact sheet.

“Improving conditions in Honduras, Guatemala, and El Salvador is a critical way to address the root causes of migration and prevent the humanitarian crisis at our border. This is a solution to many of the drivers that cause people to leave their country and move north. Cutting aid to the region will only increase the drivers and will be even more costly to deal with on our border.”

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