This week’s United Nations General Assembly, where the world’s leaders — many of them unelected despots — is a veritable rogues’ gallery. Garnering most of the critical press coverage has been the Holocaust-denying and Holocaust-prophesizing president of Iran, Mahmoud Ahmadinejad, whom Columbia University President Lee Bollinger invited onto his campus for a speaking engagement today. The gleeful way in which one of the country’s leading universities has welcomed a murderous thug to address its student body is, indeed, sickening. Across the pond, however, Prime Minister Brown is showing the sort of spine in dealing with another tyrant that ought influence how President Bollinger comports himself.

Last week, Prime Minister Brown set the stage for what is likely to become a major, transcontinental diplomatic row. In a piece for the Independent newspaper, Mr. Brown protested the Portuguese government’s decision to invite Zimbabwean dictator Robert Mugabe to Lisbon for a European Union-Africa summit in December. By doing so, the Portuguese would violate a 2002 E.U. travel ban placed on Mr. Mugabe and 130 other top Zimbabwean officials. “President Mugabe’s attendance would mean lifting the E.U. visa ban that we have collectively imposed. I believe that President

Mugabe’s presence would undermine the summit, diverting attention from the important issues that need to be resolved,” Mr. Brown wrote. He then issued an ultimatum: “In those circumstances, my attendance would not be appropriate.”

Mr. Brown’s welcome provocation puts the European Union in a delicate position: Does the E.U. anger African countries, threatening the very existence of the summit itself, or carry on its conference without the British altogether? The Portuguese justify their invitation to Mr. Mugabe on the grounds that many African governments will boycott the event if the Zimbabwean president is not allowed to participate, as occurred in 2003 when the E.U. did not invite him. Mr. Brown, however, contends that the E.U. placed a travel ban on Mr. Mugabe for a reason, to isolate his regime, and it ought to stand by its principles. In the prime minister’s words, “There is no freedom in Zimbabwe.” Mr. Brown follows in the footsteps of his predecessor, Tony Blair, who avoided the very first E.U.-Africa summit in Cairo because Mr. Mugabe had also been invited.

It is refreshing to see a major world leader take such a morally courageous stand against a dictator, especially when many of the world’s leaders so often choose fecklessness and the sort of hand wringing produced by misplaced post-colonial guilt. A source close to Mr. Brown recently told the Guardian that the plight of Zimbabwe is “a personal passion” for the prime minister. While human rights activists, Western governments, and the Zimbabwean people themselves have expressed collective disgust with the authoritarian abuses of the Mugabe regime, the same can hardly be said of Mr. Mugabe’s fellow African leaders, who continue to treat the murderous despot as a liberation hero. Already, Zambian President Levy Mwanawasa has announced that he will not attend the summit if Mr. Mugabe is uninvited, and the Tanzanian president of the Pan-African Parliament has publicly characterized Mr. Brown’s threat as “arm twisting.” South Africa’s deputy foreign minister has defended his country’s stance, saying, “All our interventions on the Zimbabwean issue have been to prevent a failed state on our doorstep.'” Meanwhile, back in Zimbabwe, the state has already failed. The International Monetary Fund reports that inflation may reach an astonishing 100,000% by the end of the year. Life expectancy — in the mid-to-late 30’s — is the lowest in the world. The just-departed American ambassador to Zimbabwe, Christopher Dell, recently predicted that Zimbabwe will collapse into anarchy by December.

At tomorrow’s Security Council meeting, Britain will ask that the United Nations appoint a special envoy to report on the human rights situation in Zimbabwe. And though Mr. Brown called upon the international community to support South African President Thabo Mbeki’s peacemaking efforts, it is clear that the British prime minister believes that South Africa’s “quiet diplomacy” has not worked and that the international community must take a more active role in solving the problem.

For too long, African leaders have treated Mr. Mugabe as a petulant child, indulging his every whim. They have complained of the West’s “confrontational” approach to Mr. Mugabe, assuring the world that Mr. Mbeki’s efforts would do the trick. But it has been seven long years since the illegal land seizures that sparked the Zimbabwean tragedy, and Mr. Mugabe’s terror shows no sign of abating.

Africa needs Europe far more than Europe needs Africa, and, lest African leaders need any reminder, the December summit is intended for the benefit of their impoverished people. If African leaders continue to once again place their loyalty with Comrade Mugabe over the fate of his oppressed people, then there ought be consequences for such a rash decision. Perhaps Western governments ought reconsider the billions of dollars in aid money they give to African governments. Either way, heeding the example of Gordon Brown — and not the gutless one of Lee Bollinger — is a good start.

Mr. Kirchick is the assistant to the editor in chief of the New Republic and reported from Zimbabwe last year.