Elliott Abrams is a senior fellow for Middle Eastern studies at the Council on Foreign Relations. He was a deputy national security adviser in the George W. Bush administration and assistant secretary of state for inter-American affairs in the Reagan administration.

Three decades ago, President Ronald Reagan convened a group of Republican and Democratic leaders — known as the Kissinger commission — and charged it to make recommendations on how the United States could best help the countries of Central America thwart Soviet- and Cuban-supported guerrilla movements by promoting democracy and economic development. Reagan faced fierce opposition from some quarters in Washington, but his policies — and the sacrifices of many U.S. friends in the region — helped bring about three decades of relative peace and economic growth in Central America.

Unfortunately, those gains are at risk. The region’s challenges today are less about ideology than about criminality and corruption that threaten to undermine democratic institutions, the rule of law and public security.

The region’s misfortune is to be caught between two countries, Colombia and Mexico, that have recently cracked down on drug-trafficking syndicates. This is wonderful — except that it has pushed those criminal organizations to move their operations to more hospitable environments. Central America has borne the brunt of this onslaught. Its countries have been overrun and overwhelmed by criminal forces that far surpass their small police forces in resources, weaponry and ruthlessness.

But this is more than an issue of wanton criminality. Narco-money is corrupting officials and institutions to create permissive environments for the cartels’ drug-smuggling operations. This corruption, at the highest levels of government, directly threatens democracy, regional security and U.S. interests.

In Honduras, voters recently turned back former president Manuel Zelaya’s attempt to return to power by rejecting the presidential candidacy of his wife, Xiomara Castro. Zelaya forfeited power in 2009 after illegal attempts to rewrite the country’s constitution. He is also dogged by accusations of ties to drug trafficking. The statistics are staggering: The State Department estimates that “as much as 87 percent of all cocaine smuggling flights departing South America first land in Honduras.” Confronting this threat requires a government willing to cooperate with the United States and its neighbors to deny haven to the narcos.

The new worry is El Salvador, which is to elect a new president Feb. 2. The Los Angeles Times reported in 2011 that “The Mexican drug gangs rapidly infiltrating Central America call El Salvador ‘El Caminito,’ the little pathway.” The State Department’s 2013 International Narcotics Control Strategy Report calls El Salvador “a major transit country for illegal drugs destined for the United States from source countries in South America.”

The presidential candidate of the Frente Farabundo Martí de Liberación Nacional (FMLN) party is former leftist guerrilla Salvador Sánchez Cerén. He faces Norman Quijano, the mayor of San Salvador and candidate of the opposition ARENA party. Four years ago, the FMLN won with a relative moderate, Mauricio Funes — but Sánchez Cerén and his allies are from the party’s toughest elements, and some of them have direct ties to drug traffickers and the government of Venezuela.

Among the key participants in the Central American drug trade is the Colombian guerrilla group FARC, which has moved over the years from “armed struggle” to narcotics. “Experts estimate that FARC takes in between $500 million and $600 million annually from the illegal drug trade,” according to the United Nations.

FARC files seized in a 2008 Colombian raid revealed intimate ties between the FARC and FMLN leader José Luis Merino, who is Sánchez Cerén’s right-hand man. Merino is “the FARC’s man in El Salvador,” according to veteran Latin America journalist José de Cordoba. The Spanish newspaper ABC reported last month how Merino helped arrange a meeting between the Italian mafia and FARC drug lords.

Merino, known as Comandante Ramiro during El Salvador’s wars, has long been a top official in the Communist Party of El Salvador and is the money man for the FMLN, directing its close ties with ALBA Petroleum, the Venezuelan government company that in El Salvador provides subsidized gasoline to FMLN-run towns. The profits from selling the gas at market prices are supposed to go into social projects, but it is widely believed that a good part of it goes to the FMLN.

“There is enough information which clearly presents Merino as someone with strong connections to the FARC,” Michael Braun, a former director of operations at the U.S. Drug Enforcement Administration, said last month. And with El Salvador now on a U.S. dollar economy and receiving nearly $4 billion in remittances from Salvadorans in the United States, the money-laundering opportunities are enormous.

The likely impact of a Sánchez Cerén victory on U.S.-Salvadoran security and counter-narcotics cooperation is dangerous. The United States has a key forward operating location in El Salvador to monitor and deter drug trafficking, and the FBI cooperates with local police against trafficking by Salvadoran gangs. Could such activities continue in light of the FMLN’s ties to the FARC and to the Venezuelan government?

Thirty years after the Kissinger commission report, democracy and peace in Central America are again at risk. This time the foreign intervention is from immensely wealthy criminal gangs. The U.S. posture of neutrality in elections is right — but our tilt toward Zelaya in Honduras in 2009 and our failure today to state our concerns about the FMLN’s drug ties can tilt elections as well. If people like Comandante Ramiro come to power, Salvadorans’ hopes for democracy and peace, and our own hopes for continuing cooperation against narcotics trafficking, may be lost.