  We address the question of the locality versus nonlocality in the
Aharonov-Bohm and the Aharonov-Casher effects. For this purpose, we investigate
all possible configurations of ideal shielding of the overlap between the
electromagnetic fields generated by a charge and by a magnetic flux, and
analyze their consequences on the Aharonov-Bohm-Casher interference. In a
classical treatment of shielding, the Aharonov-Bohm-Casher effect vanishes
regardless of the geometry of shielding, when the local overlap of
electromagnetic fields is completely eliminated. On the other hand, the result
depends on the configuration of shielding if the charge quantization in the
superconducting shield is taken into account. It is shown that our results are
fully understood in terms of the fluctuating local-field interaction. Our
analysis strongly supports the alternative view on the Aharonov-Bohm-Casher
interference that the effects originate from the local action of
electromagnetic fields.
