  We clarify the physical origin of the difference between gauge properties of
conserved currents in abelian and nonabelian theories. In the latter, but not
in the former, such currents can always be written on shell as gauge invariants
modulo identically conserved, superpotential, terms. For the ``isotopic" vector
and the stress tensor currents of spins 1 and 2 respectively, we explain this
difference by the fact that the non-abelian theories are just the self-coupled
versions of the abelian ones using these currents as sources. More precisely,
we indicate how the self-coupling turns the non-invariantizable abelian
conserved currents into (on-shell) superpotentials. The fate of other conserved
currents is also discussed.
