The only survivors in Australia were in the far western territories and roaming the desert interior in a post-apocalyptic nightmare. China had been lost only after loosing nearly a thousand nuclear weapons in the long retreat up the Yangtze Valley. Others survived in the highlands of the world, holding passes against the enemy. But few of those scattered groups were a coherent defense. Everywhere, one by one, the civilizations of the world had fallen to the remorseless invaders. With one small exception.

In the United States a combination of geographic luck — the Posleen tended to land in coastal plains and the U.S. had defendable terrain features inward of all the coastal plains — and, frankly, logistic and political preparation had permitted the U.S. government to retain control, to retain a condition of “domestic harmony” in a few areas. Of these, the most vital were the Cumberland and Ohio basins due to their industrial might and breadth of agricultural resources. The vast plains of Central Canada were still safe, and would remain so as long as the Posleen were resisted at all, for the Posleen were almost incapable of fighting in snow. But those plains, and the various western areas in human control ranging from the Sierra Madre to the Canadian Rockies, could produce only a small number of crops, mostly grains. Furthermore there was little or no industrial infrastructure in comparison to the might found in the Cumberland and Ohio.

The Cumberland, the Ohio and the Great Lakes regions were the heart and soul of the defense of the United States. Losing the Cumberland, furthermore, would open all of that up to conquest.

And with one thrust the Posleen had placed all of that in jeopardy. For years the major blow had been expected at Chattanooga, where little would stand in the way of a break-out. This battalion, and others, had defended the cities that were scattered down the range of the Appalachians, each of them, at one time or another, assaulted in force by the enemy. Only a few weeks before the battalion had been in a hair-raising battle on the Ontario Plain. But this time the Posleen had surprised everyone, striking an unnoticed and lightly defended sector, and throwing the defense of the entire Eastern U.S. into flux.