  We point out that, in a spontaneously broken U(1) gauge theory, inclusive
processes, whose primary particles are mass eigenstates that do not coincide
with the gauge eigenstates, are not free of infrared logarithms. The charge
mixing allowed by symmetry breaking and the ensuing Bloch-Nordsieck violation
are here analyzed in a few relevant cases and in particular for processes
initiated by longitudinal gauge bosons. Of particular interest is the example
of weak hypercharge in the Standard Model where, in addition, left-right mixing
effects arise in transversely polarized fermion beams.
