  A numerical simulation model of the injection and cooling of nonthermal
particles energized by shocks formed in merging clusters of galaxies is used to
fit radio and X-ray data observed from the Coma cluster of galaxies. The
results are consistent with a primary merger-shock origin for both the diffuse
radio halo emission and the hard X-ray excess measured with {\it Beppo-SAX} and
{\it RXTE}. For equal (1%) efficiency of power injected in nonthermal protons
and electrons, we predict that the Coma cluster of galaxies will be
significantly detected with the space-based observatory {\it GLAST}, and
marginally detectable with the ground-based $\gamma$-ray observatories {\it
VERITAS} and {\it HESS}. Significant TeV detections are possible if the
nonthermal proton intensity is greater due to a larger efficiency of nonthermal
hadron acceleration, or to past merger events. The nonthermal hadronic content
in Coma is also revealed by a weak, hard secondary emission component at $\sim
10$ -- 100 GHz. The spectral softening of the radio emission at large radii
from the Coma cluster core derives in this scenario from the decreasing shock
speed away from cluster center for an on-axis merger event. We discuss
differences between merger and delayed turbulence models.
