  We identify two distinct, complementary gauge field configurations for QCD
with SU(2) gauge group, one (instanton-like configurations) having to do with
chiral symmetry breaking but not with confinement, the other (regularized
Wu-Yang monopoles) very likely responsible for confinement but unrelated to
chiral symmetry breaking. Our argument is based on a semiclassical analysis of
fermion zero modes in these backgrounds, made by use of a gauge field
decomposition recently introduced by Faddeev and Niemi. Our result suggests
that the two principal dynamical phenomena in QCD, confinement and chiral
symmetry breaking, are distinct effects, caused by two competing classes of
gauge field configurations.
