Oscar Arias Sanchez at the Organization of American States in Washington on Aug. 14. (Bill O'Leary/WASHINGTON POST)

A quarter-century on, the man of peace still waits. Still waits for the broader hopes of another era to be realized. Still waits for the killing to stop.

Oscar Arias Sanchez was 46 years old when, as the improbably self-assured president of Costa Rica, he became an international phenomenon by brokering an impossible accord, knitting the presidents of five Central American nations into agreement on a peace deal that spurred the end of the civil wars ravaging the region. He always thought of the peace plan that took his name as something grander than a simple end to wars. As he puts it, the quest for a cease-fire that led to the Esquipulas II Accords, named for the Guatemalan city where they were negotiated, were merely “an overture.” But the composition’s “leitmotif” was strengthening democracy.

And this is why Arias, who paused for a leisurely chat over lunch during a recent Washington visit to celebrate the peace accord’s 25th anniversary, frets. He looks around the region he calls home and sees rampant drug violence, intractable poverty and too many democratic institutions that seem wobbly and imperiled. Now, he says, instead of mourning young “guerrilleros” — guerrilla fighters — the region’s mothers cry for slain young “pandilleros” — gang members. He touches more notes of lament than trills of triumph, so much so that I wonder aloud whether he’s depressed at what has become.

“Depressed? No,” Arias says. “Disillusioned” is a better word, he advises. “Latin America has not achieved the development that it deserves. . . . I’m not optimistic for all of Latin America, not only for Central America.”

He’s glum despite the improvements in the region — the rise of Brazil’s economy, signs of a nascent middle class and more. His emergence as a Latin American Jimmy Carteresque troubleshooter has given him a unique and dispiriting vantage point on the region’s ills, particularly the chaotic 2009 coup in Honduras, a constitutional crisis that he was called upon to help resolve but couldn’t pull off. Arias served as a mediator between Manuel Zelaya, the Honduran president who was flown to Costa Rica after that nation’s high court ordered him removed and soldiers stormed his office to force him to fly into exile, and Roberto Micheletti, the head of the National Congress who became de facto president.

“It was impossible to get Micheletti and Zelaya to sit at the same table,” Arias says. “Both were intransigent.”

The Honduran mess made Arias wary of the “specter of authoritarianism” increasing in the region, although he diplomatically avoids singling out individual countries where the powerful are trampling on democratic institutions. “With states that are so weak, there are not sufficient resources for education, health care, infrastructure and security,” he says, chiding the region’s elites for not paying enough in taxes.

At 71, Arias still has those same thick and undulating waves of hair, cleft by a neat part on his left, that appeared in news photos during his peace-planning glory days. But the strands have gone gray, and his voice, both across a table in the bar of the Mayflower Hotel and behind a lectern, can sound somber, trailing off at times, almost wistful. He is not one of those public figures particularly prone to clapping shoulders. His charisma is a subtler thing, a muted presence that somehow draws his listeners in just as persistently and effectively as a less subdued politician’s bearhug might. In a clutch of news reporters after a speech at the Organization of American States, he tightly interlocks the fingers of both hands, forming a ball beneath his chin, as though he were holding onto something that threatened to get away from him. His eyes fix on the ball of fingers before him, rather than the questioners.

A Nobel, then new dreams

Others, most notably then-Guatemalan President Vinicio Cerezo, also played major roles in shaping the peace deal in the late 1980s, but it was Arias who captured imaginations worldwide. In the library of his office in San Jose, Costa Rica’s capital, Arias hangs mementos of a lifetime spent being applauded. He holds 70 honorary degrees, but the largest honor of all was accorded to him in 1987 when he was awarded the Nobel Peace Prize. He used the prize money to start a foundation, an institution that has hosted a parade of upcoming interns and idealists over the years, many of whom were culled from elite U.S. universities, such as Harvard.

The idealist and the realist in Arias converge as the former Costa Rican president meanders into conversation about his latest dream, a peace museum he hopes to build in San Jose. The idea would be to commemorate conflicts resolved through negotiation. “There are too many war museums,” he observes. But realizing ideas such as that one take money, and Arias is hoping to collect donations in the United States to make his become reality.

The outline of the Arias saga has been clearly rendered over the years, a narrative he has been as adept at shaping as the historians. Peace vs. war. The weak vs. the powerful. In Washington, the memories flood back, for it is here, in this city of global might, that Arias — the leader of a country of just 2.6 million souls — defied an American president and cemented his place in history . Ronald Reagan was backing the contras in Nicaragua, eager to smash the threat of communism presented by Daniel Ortega’s Sandinistas, who were in league with the Soviets and the Cubans. Arias was complicating the Reagan administration’s support of a military solution by arguing for a peace deal and banking that the Sandinistas wouldn’t prove to be a sturdy threat to democracy in the region.

Looking back, Arias recalls the tense White House meetings and the showdowns with American diplomats and high-ranking officials. He liked President Reagan and Vice President George H.W. Bush, he says, and once told them that friends could disagree. He felt a particular rapport with Bush and resolved that Bush would be the first U.S. official he would tell about the peace plan. He broke the news to Bush over gin and tonics at the vice presidential residence. Bush wasn’t pleased.

Arias had a knack for displeasing U.S. officials. Reagan’s CIA director flew to San Jose to meet with him, but Arias refused to grant him an audience.

It was the peace prize, though, that gave Arias real clout. At the time, Reagan had been pressing Congress to approve more aid for the contras. But when the prize was announced, House Democratic Whip Tony Coelho declared, “This kills it; it’s dead.”

The eagle vs. the sparrow

Back then, People magazine crowned Arias “the mouse that roars for peace in Central America” and recounted how Arias stood his ground in a tense Oval Office meeting with an array of high-powered U.S. officials. “Oscar appeared like Spartacus going before the Roman generals,” Arias’s close adviser John Biehl told the magazine. Arturo Cruz, the former Nicaraguan diplomat, speaking in Washington, frames it this way: the eagle (the United States) vs. the sparrow (Arias). The sparrow, Arias says, ended up winning.

The powerful in the United States had underestimated him, Arias says. But here, he breaks off. Upstairs in his hotel room, he says, he has a book with the perfect quote to illustrate his point. He steps away from the table and disappears into an elevator, returning a few moments later, leafing through the pages. He wants to get the words exactly right. It’s an old U.S. diplomatic cable. And he reads the words aloud, a coy smile, a look of satisfaction and vindication on his face.

“Alert Ollie [North that] Pres. Arias will attend Reagan’s dinner in New York Sept. 22. Boy needs to be straightened out by heavy weights.”

That’s what they called him. Boy.