Imagine that an opposition organiser were murdered in broad daylight in Argentina, Bolivia, Ecuador or Venezuela by masked gunmen, or kidnapped and murdered by armed guards of a well-known supporter of the government. It would be front page news in the New York Times, and all over the TV news. The US State Department would issue a strong statement of concern over grave human rights abuses. If this were ever to happen.

Now imagine that 59 of these kinds of political killings had taken place so far this year, and 61 the previous year. Long before the number of victims reached this level, this would become a major foreign policy issue for the United States, and Washington would be calling for international sanctions.

But we are talking about Honduras, not Bolivia or Venezuela. So, when President Porfirio Lobo of Honduras came to Washington last month, President Obama greeted him warmly and said:

"Two years ago, we saw a coup in Honduras that threatened to move the country away from democracy, and in part because of pressure from the international community, but also because of the strong commitment to democracy and leadership by President Lobo, what we've been seeing is a restoration of democratic practices and a commitment to reconciliation that gives us great hope."

Of course, President Obama refused to even meet with the democratically elected president who was overthrown in the coup that he mentioned, even though that president came to Washington three times seeking help after the coup. That was Manuel Zelaya, a left-of-center president who was overthrown by the military and conservative segments of society in Honduras after instituting a number of reforms that people had voted for, such as raising the minimum wage and laws promoting land reform.

But what angered Washington most was that Zelaya was close to the left governments of South America, including Venezuela. He wasn't any closer to Venezuela than Brazil or Argentina was, but this was a crime of opportunity. So, when the Honduran military overthrew Zelaya in June of 2009, the Obama administration did everything it could for the next six months to make sure that the coup succeeded. The "pressure from the international community" that Obama referred to in the above statement came from other countries, mainly the left-of-center governments in South America. The United States was on the other side, fighting – ultimately successfully – to legitimise the coup government through an "election" that the rest of the hemisphere refused to recognise.

In May of this year, Zelaya stated publicly what most of us who followed the events closely already guessed was true: that Washington was behind the coup and helped bring it about. While no one will likely bother to investigate the US role in the coup, this is quite plausible given the overwhelming circumstantial evidence.

Porfirio Lobo took office in January 2010, but most of the hemisphere refused to recognise the government because his election took place under conditions of serious human rights violations. In May 2011, an agreement was finally brokered in Cartegena, Colombia which allowed Honduras back into the Organisation of American States. But the Lobo government has not complied with its part of the Cartegena accords, which included human rights guarantees for the political opposition.

Here are two of the dozens of political killings that have occurred during Lobo's presidency, as compiled by the Chicago Religious Leadership Network on Latin America (CRLN):

"Pedro Salgado, vice-president of the Unified Campesino Movement of Aguán (MUCA), was shot then beheaded at about 8.00pm at his home in the La Concepción empresa cooperative. His spouse, Reina Irene Mejía, was also shot to death at the same time. Pedro suffered a murder attempt in December 2010 […] Salgado, like the presidents of all the cooperatives claiming rights to land used by African palm oil businessmen in the Aguán, had been subject to constant death threats since the beginning of 2011."

The courage of these activists and organisers in the face of such horrific violence and repression is amazing. Many of the killings over the past year have been in the Aguán Valley in the north-east, where small farmers are struggling for land rights against one of Honduras' richest landowners, Miguel Facussé. He is producing biofuels in this region on disputed land. He is close to the United States and was an important backer of the 2009 coup against Zelaya. His private security forces, together with US-backed military and police, are responsible for the political violence in the region. US aid to the Honduran military has increased since the coup.

Recent US diplomatic cables released by WikiLeaks show that US officials have been aware since 2004 that Facussé has also been trafficking large quantities of cocaine. Dana Frank, a professor at the University of California at Santa Cruz who is an expert on Honduras, summed it up for the Nation last month: "US 'drug war' funds and training, in other words, are being used to support a known drug trafficker's war against campesinos."

The US militarisation of the drug war in the region is also pushing Honduras down the disastrous path of Mexico, in a country that already has one of the highest murder rates in the world. The New York Times reports that 84% of cocaine that reaches the US now crosses through Central America, as compared to 23% in 2006, when Calderón took office in Mexico and launched his drug war. The Times also notes that "American officials say the 2009 coup kicked open the door to [drug] cartels" in Honduras.

When I voted for Barack Obama in 2008, I never thought that his legacy in Central America would be the return of death-squad government, of the kind that Ronald Reagan so vigorously supported in the 1980s. But that seems to be the case for Honduras.

The Obama administration has so far ignored pressure from Democratic members of Congress to respect human rights in Honduras. These efforts will continue, but Honduras needs help from the South. It was South America that spearheaded the efforts to reverse the 2009 coup. Although Washington ultimately defeated them, they cannot abandon Honduras while people no different from their friends and supporters at home are being murdered by a US-backed government.

• Editor's note: Ronald Reagan's name was misspelled in the original version of this article, which was amended on 19 November 2011 at 6pm EST [11pm UK time]