  We present low temperature measurements of the resistance in magnetic field
of superconducting ultrathin amorphous Bi films with normal state sheet
resistances, $R_N$, near the resistance quantum, $R_Q={\hbar\over {e^2}}$. For
$R_N<R_Q$, the tails of the resistive transitions show the thermally activated
flux flow signature characteristic of defect motion in a vortex solid with a
finite correlation length. When $R_N$ exceeds $R_Q$, the tails become
non-activated. We conclude that in films where $R_N>R_Q$ there is no vortex
solid and, hence, no zero resistance state in magnetic field. We describe how
disorder induced quantum and/or mesoscopic fluctuations can eliminate the
vortex solid and also discuss implications for the magnetic-field-tuned
superconductor-insulator transition.
