Wrong End of Time e-bog

The time is the future. The place, an America so isolated by fear that it is cut off from the rest of the world by a massive defence system. Into this armed, barricaded state comes a young Russian scientist bearing a strange and almost unbelievable story: Superior, intelligent life - on a far higher order than any on earth - has been detected near the planet Pluto. Immune themselves by virtue of their far greater intelligence, these aliens are about to destroy the planet Earth.