Mother Jones has posted an essay by Chalmers Johnson (author of Blowback, among many others) based on his new book Dismantling the Empire. In it he argues that America's century of dominance is coming to an end whether we like it or not, and argues for dismantling our empire ourselves, and spending all the money that we are wasting overseas to solve our own domestic problems.

Let me begin by asking: What harm would befall the United States if
we actually decided, against all odds, to close those hundreds and
hundreds of bases, large and small, that we garrison around the world? 
What if we actually dismantled our empire, and came home? Would
Genghis Khan-like hordes descend on us?  Not likely.  Neither a land
nor a sea invasion of the U.S. is even conceivable.

Would 9/11-type attacks accelerate?  It seems far likelier to me
that, as our overseas profile shrank, the possibility of such attacks
would shrink with it.

Would various countries we've invaded, sometimes occupied, and tried
to set on the path of righteousness and democracy decline into "failed
states?" Probably some would, and preventing or controlling this
should be the function of the United Nations or of neighboring states.
(It is well to remember that the murderous Cambodian regime of Pol
Pot was finally brought to an end not by us, but by neighboring
Vietnam.)

Go read more.