Abstract
We present a unified gauge model of weak and electromagnetic interactions, which has the following features: (a) Chiral U(2)L×U(2)R is an exact "natural" symmetry of strong interactions in zeroth order and therefore its violations (which arise in order g4 are computable, and adjusting parameters suitably we can get (2ε0+ε8)(2ε02ε8)α; (b) violations of isospin symmetry as observed in, for example, ΔI0 mass differences are, then, computable and of order α; (c) this model can be extended to include leptons in such a way that memμ is computable and is of order g4. We also speculate on the possibility of spontaneous CP violation arising as a higher-order effect.