The Envoy

The crew of a sail boat wrecked in a storm is rescued and finds themselves held by an alien civilization under the South Pacific. The Homakuwa city of Ocealla nurses Kent (Kit) Carson and his friends back to health, and then has to decide what to do with them. Established from the rogue nation of Nueva Pacifica of generations before, Ocealla was founded when the residents of Nueva Pacifica escaped as it was destroyed by an international agreement to protect mankind and the world order.
Since then, peace and tolerance have come about with the rise of the United World Government and a new world religion led by a mystical man simply known as the Prophet. With Kit's urging, the citizens of Homakuwa with their Collective mind decide to explore the possibility of rejoining the world community. Katherine Levey, the leader of Homakuwa, leaves Ocealla to meet with ex President Ron Carson, Kit's great grandfather and the United States President during the time of Nueva Pacifica, to investigate the possibility of becoming known again. In the interim since Nueva Pacifica, the United States has been able to maintain a position of power by building the Orbiting Power System (OPS) and selling power to the world's ever-increasing appetite.
Katherine takes Ron to Ocealla to see Kit, and they decide to rejoin the world. They apply to the United World Government for membership and the approval is not without dissent. Not all world citizens are happy with the new world order. With the loss of power and control by the world's major religions, Christianity, Judaism, Islam and Hinduism, and the autocratic governments such as China and North Korea form a coalition, the Foundation and decides to disrupt the order to gain back control.
In a stunningly successful series of attacks, the Foundation strikes the United World Government. Before they are subdued, China is able to insert viruses into the central computer system that will give them eventual control.
The integration of Homakuwa proceeds, though their isolation from UWG monitoring systems is not viewed well. With their oceanographic expertise they begin directorship of the International Fishing Industry. Their genetic development ability allows them to gain the operating and maintenance contracts for the OPS, and they begin to build habitats with modified citizens designed for life in space. With power being the major impediment to China's world dominance, they strike the computer system controlling the OPS and discredit Homakuwa's ability to operate the system.
Despite not having the OPS contracts, Homakuwa continues to expand and build orbiting habitats and a lunar colony. With the discovery of a meteor swarm heading toward Earth, Homakuwa and Earth send out interceptors to try to divert the most destructive objects. They are successful with those capable of destroying the Earth, but enough smaller ones get through that civilization is devastated. During the Impact Winter, most of the life on Earth is killed, and the surface survivors and Homakuwa combine to bring it back.
Homakuwa continues to expand in orbit with the construction of more habitats. They send a number of these to Mars to colonize it, and then expand throughout the Solar System.