We present a locally supersymmetric extension of the minimal supersymmetric standard model (MSSM) based on the gauge group SU(3)C×SU(2)L×U(1) Y×U(1)′ where, except for the supersymmetry-breaking scale which is fixed to be ∼1011GeV, we require that all non-standard-model parameters allowed by the local spacetime and gauge symmetries assume their natural values. The U(1)′ symmetry, which is spontaneously broken at the intermediate scale, serves to (i)explain the weak scale magnitudes of μ and bμ terms, (ii)ensure that dimension-3 and dimension-4 baryon-number-violating superpotential operators (and, in a class of models, all ΔB=1 operators) are forbidden, solving the proton-lifetime problem, and (iii)predict bilinear lepton-number violation in the superpotential at just the right level to accommodate the observed mass and mixing pattern of active neutrinos (leading to a novel connection between the SUSY-breaking scale and neutrino masses), while corresponding trilinear operators are strongly suppressed. The phenomenology is like that of the MSSM with bilinear R-parity violation, where the would-be lightest supersymmetric particle decays leptonically with a lifetime of ∼10-12-10-8s. Theoretical consistency of our model requires the existence of multi-TeV, stable, color-triplet, weak-isosinglet scalars or fermions, with either conventional or exotic electric charge which should be readily detectable if they are within the kinematic reach of a hadron collider. Null results of searches for heavy exotic isotopes imply that the reheating temperature of our Universe must have been below their mass scale which, in turn, suggests that sphalerons play a key role for baryogenesis. Finally, the dark matter cannot be the weakly interacting neutralino. © 2009 The American Physical Society.