  We investigate two-dimensional Bose system with the long range interactions
in the presence of disorder. Formation of the bound states at strong impurity
sites gives rise to an additional depletion of the superfluid density. We
demonstrate the existence of the intermediate superfluid state where the
condensate and localized bosons present simultaneously. We find that
interactions suppress localization and that with the increase of the boson
density the system experiences a sharp delocalization crossover into a state
where all bosons are delocalized. We map our results onto the three dimensional
system of vortices in type II superconductors in the presence of columnar
defects; the intermediate superfluid state maps to an intermediate vortex
liquid where vortex liquid neighbors pinned vortices. We predict the depinning
transition within the vortex liquid and depinning induced vortex lattice/Bose
glass melting.
