The Forge of God (1987) is a science fiction novel by Greg Bear that gives a convincing account of an alien attack on Earth accomplished through misdirection and the use of self-replicating von Neumann machines. It features a character, Lawrence Van Cott, that is clearly modelled on Larry Niven.

Memorable scenes and events include the discovery of an alien in the desert, who clearly says in English, "I'm sorry, but there is bad news," and this alien's subsequent interrogation and autopsy; the discovery of an artificial geological formation and its subsequent nuclear destruction by a desperate military; and the Earth's eventual destruction by the mutual annihilation of a piece of neutronium and a piece of antineutronium dropped into Earth's core.

It is noted by some its depiction of an American President whose effectiveness is compromised by his fundamentalist religious beliefs, which are manipulated by the aliens.

There is another alien faction at work, however, represented on Earth by small spider-like robots that recruit human agents. They frantically collect all human data, biological records, tissue samples, seeds, and DNA that they can, and evacuate a handful of people from Earth. Some of the evacuees eventually settle a newly terraformed Mars while others form the crew of a Ship of the Law to hunt down the home world of the killers, a quest described in the sequel, Anvil of Stars . In space, this faction's machines combat and eventually destroy the attackers, though not before Earth's fate is sealed.

The two books show at least one solution to the Fermi paradox, with electromagnetically noisy civilisations being snuffed out by the arrival of self-replicating machines designed to destroy any potential threat to their (possibly long-dead) creators. (A similar theme is explored in Fred Saberhagen's Berserker novels.)