"OIL is the excrement of the devil," is one of Terry Karl's favourite quotes

The Stanford University professor attributes it to the Venezuelan official who inspired her to write The Paradox of Plenty: Oil Booms and PetroStates. Her book examines why so many governments have failed to convert petroleum wealth into prosperity for their citizens.

One expert she interviewed was Sheik Ahmed Zaki Yamani, the Saudi oil minister and spokesman for the Organisation of Petroleum Exporting Countries when it was putting the squeeze on western consumers in the 1970s. She asked Yamani to sum up his thoughts on what the commodity had meant for the Arab world. "All in all," he replied, "I wish we had discovered water."

Many citizens of Angola, Nigeria and Sudan to mention just three African countries where the blessings of oil have been decidedly mixed would surely agree.

Last week the Institute for Advanced Strategic and Political Studies in Washington drew a large crowd when it hosted a seminar on African oil. Speakers included the assistant state secretary for Africa, Walter Kansteiner, and congressman Ed Royce, the energetic California Republican who chairs the house's Africa subcommittee, and Karl.

A decade after the Gulf war, the events of September 11 have been another reminder that life might be simpler for the US if it could do without oil from the Middle East, the source of 24% of its imports. Half comes from producers like Canada, Mexico and Venezuela. The Gulf of Guinea accounts for 14%.

"African oil should be treated as a priority for US security postSeptember 11," said Royce. Geographically the reserves of Nigeria, Angola and Equatorial Guinea are much closer to the US refineries than the Arabian peninsular.

It was "very, very difficult to imagine a Saddam Hussein in Africa". And, if there was trouble, good news: "Most of the production is offshore."

President George Bush is close to the US oil industry. With projections showing that the Persian Gulf will still be supplying between 54% and 67% of the world's oil in 2020, the administration is serious about diversifying US sources. This is a major factor in Bush's Africa policy.

The question is: how far will the administration go in supporting demands that the oil enrich, rather than poison, the societies to which it belongs?

Royce, who is taken seriously by the Bushies, says governments must account for how they spend their oil revenues, though he avoids insisting, as groups like Global Witness have done, that the oil companies disclose what they are paying the governments.

He contends that the companies have a duty to "invest in human capital, training staff at all levels" in countries where they operate, but allows that, realistically, they can do little more than "nudge" their hosts on human rights and governance. Those issues should more properly be pushed by regional groupings like the African Union and the Southern African Development Community, he feels.

Royce approves of the model developed for spreading the benefits of the Chad-Cameroon oil field and pipeline project. In return for World Bank support, the participants are subject to monitoring by an independent advisory group.

The authorities must prepare detailed plans for using revenue to benefit their people.

In theory, governments, companies and local interest groups are forced to work together.

This model might have only limited application. Chad is landlocked. Its oil is worth little unless it can be piped 1070km to the sea. It is desperately poor. To exploit its resource it must rely on the finance, and conditions, of strangers.

Other African oil producers are less subject to leverage. Foreign companies are scrambling for concessions, mostly offshore, for the development of which they can readily find partners and finance without turning to picky institutions like the World Bank.

And with most of the wells out to sea, no one's land is fouled or taken. The state's subjects are not constantly reminded that millions of dollars a day are being sucked out of their patrimony to somewhere where it does not benefit them.

Royce hopes the coastal oil producers will use the African Growth and Opportunity Act's trade preferences to diversify their exports, using oil revenues to invest in infrastructure and their people. So far it is not happening. The countries' nonoil exports, negligible to begin with, have generally declined since the act came into effect.

A recent International Monetary Fund paper based on an analysis of 36 African countries found a strong correlation between bad economic policy and resource endowment. "Good policies are costly" to such governments "since lower taxation, lower tariffs (and) less state control of the economy" needed to promote diversification "tend to reduce the fraction of the national surplus that the ruling elite can extract".

That Venezuelan was right. Oil is the devil's excrement.

Will the Bushies try to make it less vile in Africa?