Another sf technicolor extravaganza along the lines of The Mote in God's Eye (1974) and Lucifer's Hammer (1977), but more tedious and less thoughtful than either. In the near future, an uncommunicative alien spaceship approaches Earth--then, without warning, launches a devastating attack. Soon Earth, robbed of its ability to retaliate against space-based weapons, is apparently defeated; an alien army occupies Kansas, taking captives and plunder. The alien ""fithp"" turn out to resemble baby elephants with bifurcated trunks bearing digits capable of manipulating objects--but they're a fairly dimwitted bunch: they enforce a bizarre surrender ritual on their prisoners, confidently expecting them to stay surrendered. (They didn't invent their own technology but derived it from vanished ""Predecessors."") And then, in a last-ditch co-operation between Earth's super-powers, nuclear missiles wipe out the aliens in Kansas. So the fithp drop a huge asteroid, the ""foot,"" in the Indian Ocean, devastating vast areas and dramatically affecting the world's climate--while the US government, secure beneath the Rockies and advised by a panel of sf writers, frantically builds a nuclear-powered spaceship. . . for a showdown with the giant alien mother-vessel. Niven and Pournelle provide a plausible enough outline, with the alien society particularly well worked-out. But the dozens of subplots are often barely relevant; there's a cumbersome cast of thousands and some ""Star Wars"" message-mongering; and there's little tension or excitement except in the closing moments. Overblown and largely underdone, yet sure to reach most of the Lucifer's Hammer audience.