At the United Nations, there are, as you’d expect, flagrantly pointless press briefings going on in some wing or another, concerning some topic or another, at any given hour of the day. The diplomats and reporters accept the custom with knowing smirks and lazily upraised hands. It’s the standard kabuki. Except, that is, when Reverend Miguel d’Escoto Brockmann is speaking. The president of the U.N. General Assembly, d’Escoto has apparently decided, at age 76, that he has no time left for politesse, and his briefings are another animal entirely--the kind of invective-laced bravura jags perfected by Fidel Castro and Hugo Chavez, who, as it happens, are two of d’Escoto’s heroes.

Take a March showing the Nicaraguan priest and onetime Sandinista put on after returning from a tour through Asia and Europe, during which he had cozied up to Iranian President Mahmoud Ahmadinejad and defended Sudanese President Omar Al Bashir against Darfur-related war crimes charges. Back in New York and pressed by reporters about such controversial stands, he scoffed at Washington’s demonization of Ahmadinejad, given its “canonization of the worst of dictators,” like Marcos and Pinochet. He blamed the United States for undermining the United Nations in the run-up to the Iraq war. He suggested that the Bashir indictment was racist and tied it (and, if his furrowed brow and hand-waving were any indication, the Darfur carnage itself) to the White House. “Who first raised the issue of genocide?” he said. “Bush. George W. Bush. That should tell you quite a bit already.”

What made this monologue so startling was that it appeared not in the dark days of the previous U.S. administration, but in the early euphoria surrounding Barack Obama. Indeed, at this point Susan Rice, Obama’s ambassador to Turtle Bay, could take on a full-time staffer for the sole purpose of reprimanding d’Escoto. In March, her deputy told The Washington Post that he “has repeatedly abused his position to pursue his personal agenda, and in doing so he diminishes the office and harms the General Assembly.” Herein lies the challenge for the Obama administration: To make good on its promise of better using the United Nations, it doesn’t just need to navigate the power politics of the Security Council. It must figure out how to manage diplomats like Reverend d’Escoto and the restiveness in the U.N. ranks he represents.

When its soporific secretary-general, Ban Ki Moon, began work in 2007, the United Nations was in arguably the worst shape of its 60-year history--a byword for political impotence, with the war in Iraq stumbling into its fifth year and the rockets flying in Gaza, and a possible breeding ground for corruption, with Kofi and Kojo Annan having been investigated in the Oil-for-Food scandal. The contempt for the place expressed over the years by the likes of Daniel Patrick Moynihan and Jeane Kirkpatrick, to say nothing of John Bolton, suddenly seemed all too justified. Even devoted internationalists and liberals found themselves asking whether it still served a purpose. What was desperately needed, it was agreed, was a revitalizing figure, a post-cold-war Dag Hammarskjold who could make the United Nations relevant again.

Ban is emphatically not that figure. He began work in 2007 with little fanfare and has governed with less. In certain quarters, the beleaguered Korean is known as Ban Ki Who? And that quiescence has left an opening through which d’Escoto has charged--carrying all the baggage from his colorful past.