  The solution of the axial U(1) problem, the role of the topology of the gauge
group in forcing the breaking of axial symmetry in any irreducible
representation of the observable algebra and the theta vacua structure are
revisited in the temporal gauge with attention to the mathematical consistency
of the derivations. Both realizations with strong and weak Gauss law are
discussed; the control of the general mechanisms and structures is obtained on
the basis of the localization of the (large) gauge transformations and the
local generation of the chiral symmetry. The Schwinger model in the temporal
gauge exactly reproduces the general results.
