Detailed measurements have been made of the magnetic field (0<H<6 T) and temperature (10 K<T<100 K) dependencies of the critical current densityjcin Tl2CaBa2Cu2O8films before and after irradiation with incremental fluences (0<&Fgr;<3×1016cm−2) of 2 MeV protons. The results are interpreted quantitatively in terms of radiation‐induced changes in (1) the critical temperature, (2) the rate of thermal flux creep, and (3) local scale superconductivity. Radiation‐induced enhancements injcare described by an expression which allows the fluence that maximizesjcto be predicted as a function ofH,T, pinning energy, and particle type.