  The contribution of a $K^*(1430)$ $0^+$ resonance to $D^0\to K^-\pi^+$ is
calculated by applying the soft pion theorem to $D^+ \to K^* \pi^+$, and is
found to be about 30% of the measured amplitude and to be larger than the
$\Delta I=3/2$ component of this amplitude. We estimate a 70% contribution to
the total amplitude from a higher $K^*(1950)$ resonance. This implies large
deviations from factorization in D decay amplitudes, a lifetime difference
between D^0 and D^+, and an enhancement of $D^0-\bar D^0$ mixing due to SU(3)
breaking.
