Jacob Zuma, the controversial former deputy president of South Africa, was elected leader of the African National Congress last Tuesday. He will likely become the next president of South Africa in two years — a prospect many fear.

Yet, the Zuma presidency could prove a blessing in disguise. South Africa needs an open debate on key issues such as AIDS, unemployment and crime. Mr. Zuma’s shortcomings are well known. He will find it more difficult to stifle debate and discontent the way his predecessor did. That is good news for South African democracy.

When Mr. Zuma was fired as South Africa’s deputy president in June 2005, he was an object of widespread ridicule. He stood accused of corruption and rape. When pressed on the latter charge, Mr. Zuma admitted to “showering” after having sex with an HIV-positive woman in order to ward off infection. Both charges were later dismissed.

Though Mr. Zuma may face further corruption charges next year, his rise to the ANC’s top is nothing short of spectacular. But what does his ascendancy hold for South Africa?

First, Mr. Zuma won the leadership of the ANC in the first contested election in 58 years. The divisiveness of the battle with his former boss, Thabo Mbeki, will leave the ANC’s Stalinist internal discipline in tatters.

Dissent within South Africa’s dominant party is to be welcomed. When Mr. Zuma becomes the country’s president, the defeated faction might try to weaken him. An obvious way to do so would be to help the opposition parties in parliament hold the executive branch accountable on issues such as corruption and misgovernment.

After years of acting as Mr. Mbeki’s rubber stamp, the parliament will have a golden opportunity for self-assertion.

Second, Zuma’s presidency will likely free up the public discourse in the country. Since coming to power in 1999, Mr. Mbeki’s has pursued two political goals. One was the monopolization of power in his hands and second was the silencing of his opponents inside and outside of the ANC. Internal dissenters, like Cyril Ramaphosa and Tokyo Sexwale, were neutered after groundless accusation of plotting to assassinate Mr. Mbeki himself.

External dissenters, like the opposition Democratic Alliance and various civil society groups, were weakened by persistent accusations of racism and lack of patriotism. By and large, the public debate ground to a halt.

Unlike Mr. Mbeki, who remained detached and inscrutable throughout his presidency, Mr. Zuma’s shortcomings are well known. He has been subjected to criticism and ridicule that will not go away when he enters the Union Building in Pretoria. That too is good news. South Africa’s murder rate is 9 times higher than that of the United States and its HIV/AIDS pandemic afflicts 19 percent of its people between ages 15 and 49. The number of people living in absolute poverty has doubled since 1994. Put simply, South African politicians have much to be criticized for.

Third, Mr. Zuma will try to restore his credibility and build his gravitas both domestically and internationally. As such, he will likely maintain those policies of his predecessor for which Mr. Mbeki was justly praised. For example, South Africa’s macroeconomic stability, Mr. Zuma’s recent speeches in the United States and at home indicate, will be left unmolested. Conversely, Mr. Zuma will likely jettison policies for which Mr. Mbeki was justly criticized. Among them are HIV/AIDS denialism and support for Robert Mugabe of Zimbabwe.

Considering that the “shower” episode almost killed his political career, Mr. Zuma will need to show maximum sensitivity to the skeptical anti-AIDS activists. The change of track on Zimbabwe should be comparatively easy.

The Congress of South African Trade Unions, which was crucial to Zuma’s victory on Tuesday and which is closely allied with Mr. Zimbabwe’s Movement for Democratic Change, was critical of Mr. Mbeki’s “quiet diplomacy” and will demand a firmer stance on Mr. Mugabe. Unfortunately, the increased influence of the trade unions will also likely eliminate any possibility of a labor market reform.

That is unfortunate, because South Africa suffers from many well-meaning but ultimately harmful regulations that keep unemployment high at 26 percent.

The African continent has been plagued by the “big-man” rule since the 1960s. Under Mr. Mbeki, South Africa’s democratic institutions seemed threatened and strained. True, democracy often fails to bring to power the most worthy individuals, but it is still the best system we have to keep those in power in check. Zuma may be a flawed man, but the change of leadership will do South Africa a world of good.