The ups and downs of Mr Richardson's African voyage seem to have convinced Washington there is a real risk of a bloody battle for Zaire's capital, Kinshasa, and that it would be unwise to rely on the rebel leader, Laurent Kabila, for a peaceful transfer of power, or for any subsequent period of stability based on democratic and free-market principles.
Over the past few days, US officials have broken an uneasy silence about Mr Kabila to give a decidedly ambivalent, if not negative, assessment. Reference is made to his Marxist past, inexperience of government and his "unreliability".
Some of this may stem from the rebel leader's decision not to turn up on the first day of talks with President Mobutu last week, after extravagant efforts had been made to transfer an ill and reluctant Mr Mobutu to the ship for the talks venue.
Mr Kabila's non-appearance was all the worse for the US because Mr Richardson had helped to broker the meeting and presented it as a breakthrough. Whatever the reason, recent American comments seem to mark a cooling in Washington's appraisal of Mr Kabila, and of Zaire's chances of a peaceful transfer to democracy under his leadership. The State Department spokesman, Nicholas Burns, even went on record to urge Mr Kabila to show responsibility.
"Mr Kabila understands what's at stake for him is his reputation," said Mr Burns. "He needs to think about being a responsible person who can lead the government. In anticipation of that, he needs to think about ways to preserve life."
This is a far cry from the US mood when Mr Richardson set out for Zaire. Then, State Department-spun news broadcasts said the envoy was setting out to "ease" the conflict in Zaire. Now US ambitions are more modest. Officials set out a list of priorities for US diplomacy. They were to prevent bloodshed in Kinshasa in the event of a rebel takeover, to ensure the smooth repatriation of refugees to Rwanda, and to see human rights were respected.
The only refinement to this list is the hope that a peaceful transfer of power can be engineered by means of a "broad, inclusive transitional government" that would lead to democratic elections. Less than two months ago, Washington had confidently recommended elections before the rebel forces reached Kinshasa.
US officials are sensitive about suggestions that Washington was slow, accidentally or on purpose, to react to events in Zaire, or that it barged in on a peace-making show that belonged to Mr Mandela.
They deny Washington stood idly by, saying it initiated direct contacts with the rebels from an early stage. One possible channel, improbable though it sounds, may have been the television evangelist, Pat Robertson, who made a number of trips to rebel-held areas in private planes, ostensibly to see about his mineral interests.
Another unofficial envoy, confirmed by diplomatic sources, was President Bill Clinton's wife, Hillary, who was charged with conveying the message that the US would be "helpful where it could be", when she met Mr Mandela on her African tour last month.
There is sensitivity in Washington, too, about reports of friction with France, which fears the US is taking over France's role as regional power- broker. The French ambassador to Zaire was pointedly not invited to the Mobutu-Kabila talks and diplomatic sources in Washington predict difficulties with Paris if the "broad, inclusive transitional government" favoured by the US excludes all Mobutu associates.
There is consolation for France. While the end of President Mobutu's rule spells the end of France's dominant role in Central Africa, the inconclusive results of Mr Richardson's diplomacy make it premature to talk of the US taking over that position.Reuse content