How are liberal institutions destroyed? These days, no military coup is necessary. Instead, cynical and determined rulers aim to corrupt rather than abolish independent courts, legislatures and media — and their defenders are too divided, too weak or too distracted to respond effectively.

Latest case in point: the Inter-American Commission on Human Rights, a half-century-old multilateral body that has played a major role in the promotion of freedom in the Western hemisphere — and is in imminent danger of being gutted. At a meeting in Washington this month, foreign ministers of the Organization of American States (OAS) will consider a series of “reforms” to the commission and its office on freedom of expression that would have the effect of defunding or blocking what has been the OAS’s most visible and effective work, from the defense of indigenous groups to the protection of journalists.

Behind the assault — no surprise — are the leftist populist rulers of Venezuela, Ecuador and Nicaragua, who have spent the last few years gutting democratic institutions in their countries and now seek to punish the Inter-American Commission for calling attention to their offenses. At the head of this pack is Rafael Correa, the 49-year-old president of Ecuador and would-be successor to the dying Hugo Chavez as Latin America’s chief caudillo and Yanqui-baiter.

Correa has exceeded even Chavez and Nicaraguan President Daniel Ortega in his persecution of journalists, whom he has variously fined, expropriated and subjected to spurious lawsuits in rigged courts. Called out by the commission’s courageous rapporteur on freedom of expression, Catalina Botero Marino, Correa has made it his personal mission in the last 18 months to destroy both her operation and the commission — and he is quite close to succeeding.

Correa traveled to an OAS ministers meeting in Bolivia last June to lobby for his measures, which would take away most of the funding from the freedom of expression office, stop the commission itself from issuing critical reports on major rights violators such as Ecuador and severely restrict its “protective measures,” which it uses to defend civil-society activists and other targets of abuses. The Ecuadoran won the de facto cooperation of OAS Secretary General Jose Miguel Insulza, a Chilean socialist who agreed to allow the OAS assembly to impose reforms on the commission by majority vote — in violation of its charter.

Venezuela and its allies — including tiny countries in the Caribbean to which it delivers precious subsidized oil — together control 15 votes in the OAS and need only three more to push their measures through. At the Bolivia meeting, they won a motion for their proposals to proceed by an overwhelming vote — with only the United States, Canada and Costa Rica dissenting.

Wait, you say: The vast majority of OAS countries are liberal democracies, including such economic and political heavyweights as Brazil, Mexico, Colombia and Chile. Surely they can stop this Ecuadoran gadfly, whom they commonly regarded as a buffoon?

Yet that’s where the real trouble starts. Though their own media are robustly free and their courts are fair, the region’s democratic governments have been sluggish, at best, in their defense of the commission. Even those free media have failed: The threat to the commission has been virtually ignored up until now by the U.S. and Latin American press.

Everyone has a reason to overlook or tolerate the attack on the commission. Brazil is still angry about a 2011 commission measure that — rightly — pointed out that a hydroelectric dam project was trampling on indigenous rights. (A Brazilian judge later drew the same conclusion, but President Dilma Rousseff, who was energy minister at the time, still seeks revenge.) Peru didn’t like a commission investigation into the 1996 seizure of the Japanese Embassy in Lima by a terrorist group. Chile is wary of taking on the Venezuela bloc, lest it retaliate by raising the claims on Chilean territory of Bolivia.

And the United States? Washington is hamstrung in part because it has never ratified the American Convention on Human Rights, under which the commission operates. But more broadly, the Obama administration has been absent on such hemispheric issues. As in other parts of the world, its policy amounts to excuses for passivity: Robust diplomacy against the Correa campaign, it is claimed, would only produce a backlash. So the U.S. ambassador to the OAS offers up empty statements about Washington’s support for freedom of expression — and one of the world’s most robust human rights institutions twists in the wind.

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