The Sheep Look Up is a work of speculative fiction written by the late and lamented John Brunner in the late '70s. It's set in a bleak future in which the world totters on the brink of evironmental collapse, America is governed by a charismatic but idiotic jingoist of a President who is easilly manipulated by his cabinet, who has gradually alienated the rest of the world through agressive foreign policy and unwillingness to abide by basic environmental standards. The police have become ever more repressive in their efforts to stop the occasionally violent protests of a loose-knit group of fiercely environmentalist anarchists. Gosh, it sure is a good thing none of that happenned.
The Sheep Look Up was the middle book of a trilogy of futurist social fiction by Brunner, the first book of which was Stand on Zanzibar, and the third the equally prescient The Shockwave Rider. The Sheep was indubitably the darkest of the three, and arguably the most relevant; oddly enough, it is the only one which is now out of print, though a bit of poking around in a decent used book shop or library should turn up a copy quickly enough.
The title, incidentally, as well as the epigraph, are from "Lycidas", a poem by William Blake. The full epigraph is:
The hungry sheep look up and are not fed,
But swoln with wind, and the rank mist they draw,
Rot inwardly, and foul contagion spred