Death Quotient and Other Stories

Martin Rhode, a distinguished soldier of one of Earth's warring states, has been unwittingly captured by aliens after innocently exploring a hole caused by what was perceived to be enemy warfare. As it turns out, the aliens are being pursued by natives of an enemy planet and they have sought refuge on Earth. They do not plan on staying long, however, but actually intend to lure their rivals in so that they may all be destroyed along with everyone else on the planet, by a special weapon they are at that moment creating. Martin Rhode appeals to the aliens, and they allow him to send a warning to all Earth people that it will soon be the end of the world. 

At first disbelieving, warring states and individuals afterwards realize their mistakes and immediately reconcile with each other, and make plans on solving the imminent problem that they face that of expelling the alien presence in their midst!
Also includes the stories: ALL OUR YESTERDAYS, DELUSION DRIVE, THE GREAT STONE DEATH, MINION OF CHAOS, COMMON DENOMINATOR, THE MINIATURE