ON SATURDAY Nigeria inaugurated its first elected president in 15 years. At such times it's customary to focus on challenges facing the new regime, and the obstacles looming on President Olusegun Obasanjo's path are frighteningly high. But before moving on to gloomy contemplation of Nigeria's troubles, it's only fair to celebrate for a moment the nation's success in coming this far. One year ago, with the death of corrupt dictator Sani Abacha, few would have predicted it.

Interim ruler Abdulsalami Abubakar did promise from the start a transition to democracy. But Nigeria had heard many such promises in the past, including from generals like Mr. Abubakar, and most of them had come to naught. This time, though, the general kept his word. He released most political prisoners (though the most prominent of them, Moshood Abiola, died while still in captivity). He lifted the lid on political parties and allowed local and then national elections. Mr. Obasanjo, himself a former general, was chosen in an election hardly free of fraud but fair enough, in the opinion of many observers, to roughly reflect the popular will.

Now the hard work begins. Nigeria, Africa's most populous nation, was once among its most hopeful, but its prospects have steadily declined. Gasoline shortages in this oil-rich country became a symbol of economic mismanagement. Venality ruled. Most of the institutions that help a country function -- political parties, the civil service, the military, the educational establishment -- have been corrupted or degraded by years of arbitrary military rule. A decline in the nation's foreign reserves from about $7 billion last June to $3.1 billion by the end of April indicated that the wholesale looting by corrupt generals and their friends didn't stop with Mr. Abacha's death.

Today most Nigerians are poor. AIDS is a huge problem. Regional and tribal rivalries divide the country, and resentment is understandably intense among the long-oppressed residents of oil-producing regions. Nor is there any longer much of a political class with the training and experience to grapple with these problems.

All of which means the rest of the world should pitch in as much as possible. The inauguration of a democratic government is only a first step. If it succeeds, it could set a powerful example throughout western Africa.