The Grand Tour: Moonwar by Ben Bova hardcover 1997

Ben Bova's extraordinary Moonbase Saga continues with a breathtaking near-future adventure rich in character and incident. Seven years after the indomitable Doug Stavenger has realized his cherished dream of establishing a colony on the inhospitable lunar surface, Moonbase is a thriving community, a marvel of scientific achievement created and supported by nanotechnology: virus-sized machines that can build, cure, and destroy. But nanotechnology has been declared illegal by the home planet's leaders, and a powerful despot is determined to lay claim to Stavenger's peaceful city--or obliterate it, if necessary. The people of Moonbase, a colony with no arms or military, must now defend themselves from earthborn aggression with the only weapon at their disposal: the astonishing technology that sustains their endangered home.