  We calculate one loop contributions to $\Gamma(h \rightarrow \gamma \,
\gamma)$ from higher dimensional operators, in the Standard Model Effective
Field Theory (SMEFT). Some technical challenges related to determining
Electroweak one loop "finite terms" are discussed and overcome. Although we
restrict our attention to $\Gamma(h \rightarrow \gamma \, \gamma)$, several
developments we report have broad implications. Firstly, the running of the
vacuum expectation value modifies the $\log(\mu)$ dependence of processes in a
manner that is not captured in some past SMEFT Renormalization Group (RG)
calculations. Secondly, higher dimensional operators can source ghost
interactions in $R_\xi$ gauges due to a modified gauge fixing procedure.
Lastly, higher dimensional operators can contribute with pure finite terms at
one loop in a manner that is not anticipated in a RG analysis. These results
cast recent speculation on the nature of one loop corrections in the SMEFT in
an entirely new light.
