Diphoton Revelation of the Utilitarian Supersymmetric Standard Model

In 2002, I proposed a unique $U(1)$ extension of the supersymmetric standard model which has no $\mu$ term and conserves baryon number and lepton number separately and automatically. This model, ${without~any~change}$, has all the necessary and sufficient ingredients to explain the possible 750 GeV diphoton excess, observed recently by the ATLAS Collaboration at the Large Hadron Collider (LHC). It is associated with the superfield which replaces the $\mu$ parameter. If confirmed and supported by subsequent data, it may even be considered as the first evidence for supersymmetry.