Urbanization, rising income inequality, and increasing class segregati
on have produced a geographic concentration of affluence and poverty t
hroughout the world creating a radical change in the geographic basis
of human society. As the density of poverty rises in the environment o
f the world's poor, so will their exposure to crime, disease, violence
, and family disruption. Meanwhile the spatial concentration of afflue
nce will enhance the benefits and privileges of the rich. In the twent
y-first century the advantages and disadvantages of one's class positi
on will be compounded and reinforced through ecological mechanisms mad
e possible by the geographic concentration of affluence and poverty, c
reating a deeply divided and increasingly violent social world.