  We estimate electromagnetic (ultra-peripheral) and strong contributions to
dAu soft coherent inelastic diffraction at RHIC, dAu \to X Au. We show that the
electromagnetic contribution is the dominant one and that the corresponding
cross section is sizable, \sigma^{dAu \to XAu}_{\rm e.m.}=214 mb, which
constitutes 10% of the total dAu inelastic cross section.
