In his first meeting with President Bush, Sergio Vieira de Mello in March made headlines when he scolded America for keeping some 650 alleged Taliban and Al Qaeda members at Guantánamo Bay in a "legal black hole," without formal charges.
While acknowledging the "insidious threat" of terrorism, the UN High Commissioner for Human Rights recalled in a recent BBC interview that he told Mr. Bush "you can be as effective in fighting terrorism and ... do not need to suspend certain fundamental freedoms and guarantees to achieve that goal."
As human-rights chief, Mr. Vieira de Mello wields the power to "name and shame" perceived violators. But the UN official, praised for jump-starting new governments in war-torn Kosovo and East Timor, will take a four-month hiatus from his post for the more political role of UN envoy in Baghdad. He expects to arrive Monday in the midst of a US effort to put a more multinational face on an increasingly complicated occupation.
Some observers caution that the need for good working relations with the US civilian administrator, L. Paul Bremer, may induce Vieira de Mello to mute public criticism.
Even on human rights in Iraq, which Vieira de Mello himself described last week as "fundamental to stability and true peace," some observers have questions.
Amnesty International, for example, says it has received "a few testimonies" from Iraqis alleging "ill treatment or torture" during interrogations by US and British soldiers.
"The crux of the matter is, as high commissioner we would expect Sergio Vieira de Mello to speak out fully on all questions of concern," says Yvonne Terlingen, Amnesty's representative at the UN. "But as special representative, it is a political post where human rights is only one of the considerations. And that complicates matters."
While in Baghdad, Vieira de Mello will oversee the UN's humanitarian and reconstruction efforts, with an as-yet-undetermined role in creating a transitional Iraqi government. One immediate goal, the debonair Brazilian told media this week, is to foster better relations with the "coalition authority" - mainly the US and Britain. Months of vitriol over Iraq split the UN Security Council and sidelined it during the war. A new UN resolution last week ended sanctions against Iraq and recognized the coalition's rule. Officials on all sides say they want to patch up relations. The US could also use the help, say analysts.
"There are terrible problems in Iraq, for which no one is quite certain what the best solutions are," says Jeane Kirkpatrick, who was Ronald Reagan's first representative to the UN and now holds a senior position at the American Enterprise Institute. "Vieira de Mello is a smart, intelligent, experienced man, and the Americans are sufficiently pragmatic and problem-solving oriented to recognize that there will be an opportunity for him to make valuable contributions."
Still, several issues may reignite US-UN hostilities. In that same BBC interview, he warned the US not to impose its will amid speculation it was drafting a new Iraq constitution and would hand-pick its new leaders. The human-rights chief also said he would investigate alleged US violations of the Geneva Conventions, which outline the rules of warfare and treatment of prisoners.
Vieira de Mello started at the world body in 1969 with the UN High Commission for Refugees. UNHCR assignments over the next decade took him to hotspots like Bangladesh, Sudan, Cyprus, Mozambique, and Peru. The troubleshooting continued in 1981 with a two-year stint as political adviser to the UN Interim Force for Lebanon, a peacekeeping unit established soon after Israel's invasion of Lebanon.
In 1999 came his most challenging assignments: the first UN administrator in Kosovo, and a few months later, the top UN job in newly liberated East Timor.
"Sergio focuses on the value of success more than he fears failure," says David Malone, former Canadian ambassador to the UN and president of the International Peace Academy, where Vieira de Mello is a board member. "He is a man of action, oriented toward results and very decisive, which is quite atypical of UN officials."
Vieira de Mello also learned the value of quiet diplomacy, he told Reuters last year. He was not available for interviews this week.
"Public recriminations may not always be the best means of achieving a goal," Vieira de Mello said then. "Through discreet negotiations you can obtain results that you might not have obtained through public statements or finger-pointing."
Such discretion may be one reason Kofi Annan tabbed him last year to be High Commissioner for Human Rights, among the most politically sensitive jobs at the UN. Former Irish President Mary Robinson had reportedly ruffled too many feathers when naming and shaming.
At this point, US officials say they will welcome him, for he lends legitimacy to the entire operation. "It's always easier to criticize from the outside, but once we have someone from the UN on the ground, it will clear up some misconceptions about what our objectives are," says a State Department official. "We're already thinking exit strategy, and part of that is having critical support from the UN and the international community."