Washington ? Africa once carried a world of hope on broad continental shoulders that stretch from Casablanca to Suez. But a continent of promise quickly became a zone of failure and despair. Today Africa struggles to escape back to the future it left behind.

The brutal tragedies of Sudan and Zimbabwe underline the enormous challenges Africans confront in this task. But now there are also perceptible stirrings of change that suggest Africa’s fate is not immutably fixed as one of ruin and tyranny.

In Kenya, for example, the democratically elected government that ended the corrupt rule of Daniel arap Moi in 2002 is writing a new constitution that will have significant input from the wananchi, or the people — if the determined Kenyan woman who won the 2004 Nobel Peace Prize has her way, which I gather she usually does.

“The people are learning that you cannot leave decisions only to leaders,” says environmentalist Wangari Maathai, whose Green Belt Movement was creatively recognized by the Nobel jury for contributing to world peace. “Local groups have to create the political will for change, rather than waiting for others to do things for them. That is where positive, and sustainable, change begins.”

Maathai was in Washington this week to address the Women’s Edge Coalition, an advocacy group that concentrates on economic issues. On the day we talked, a very different kind of event was occurring in South Africa to turn the clock — or at least the mind — back to what might have been.

It was the announcement of the biggest foreign investment yet made in South Africa under the post-apartheid African National Congress government — a $5.5 billion vote of confidence in that country by Barclays Bank of Britain.

Barclays is not just any old company in the South African context. The bank thrived under the white minority regime until investor boycotts and political instability in South Africa forced Barclays to close operations there in 1986. Now it has come back to buy a 60 percent stake in the country’s largest retail bank, Absa Group, while agreeing to emphasize black empowerment in its work force.

Barclays officials emphasize that they have returned because they have been impressed by how well governments headed by Nelson Mandela and his successor, Thabo Mbeki, have managed the economy. The bankers add that Barclays intends to expand its banking network throughout Africa from its southern base.

These are not wooly idealists talking. But it takes business and civic visionaries to look beyond the ruins left by Moi, Idi Amin, Mobutu Sese Seko, Jean-Bedel Bokassa and the other corrupt and tyrannical African rulers who exploited and betrayed the unrealistic hopes of the late 1950s and early 1960s. In Zimbabwe, Robert Mugabe continues the tradition with, alas, Mbeki’s complicity.

But new hope is generated by a spreading revulsion among Africans themselves over the excesses visited upon them. That reaction is reflected in the Nigerian government’s reform efforts under Olusegun Obasanjo and by the rise in Kenya of a leader like Maathai. She is a consensus-minded, highly articulate community organizer who has gone from being jailed and beaten by the old regime for her dissent to being a member of the present Cabinet.

When I asked her about the troubled Darfur region of Sudan, Maathai argued that it is not only possible for Africans to take the lead in resolving that humanitarian crisis, but essential for them to do so.

“Darfur is an example of a situation where a dire scarcity of natural resources is manipulated by politicians for their own ambition. To outsiders, the conflict is seen as tribal warfare. At its roots, though, it is a struggle over controlling an environment that can no longer support all the people who must live on it,” Maathai said.

“You must not deal only with the symptoms. You have to get to the root causes by promoting environmental rehabilitation and empowering people to do things for themselves. What is done for the people without involving them cannot be sustained.”

Maathai’s Green Belt Movement has organized the reforestation of areas in Kenya that had been stripped of trees by commercial farming, population pressures, drought and unwise policies of land ownership and management.

“We are very fond of blaming the poor for destroying the environment. But often it is the powerful, including governments, that are responsible,” said Maathai, who studied biological sciences in the United States, Germany and Kenya.

Africa’s false start punished those who expected too much from it. But it would be unworthy to compound that error now by expecting too little.