From Zaire, ailing dictator Mobutu Sese Seko and rebel leader Laurent Kabila prepare today for face-to-face talks at sea, with Kabila insisting the veteran strongman must stand down after three decades in power. Zairian officials said the meeting, initially planned for tomorrow, would take place on Saturday. The venue remains a South African navy ship in international waters off Africa. And as the Zairian government continues what appears to be a rapid disintegration, the U.S. State Department is showing increasing misgivings about Laurent Kabila, the rebel chieftain who aspires to be the country’s next leader. Spokesperson Nicholas Burns said yesterday that he lacks democratic credentials, and he noted that a series of abuses, including atrocities, have been committed against Rwandan refugees in territory controlled by Kabila’s forces. The U.S. government has yet to document and chronicle the abuses of the more than 30-year reign of the dictator they supported, Mobutu Sese Seko.