  Particles that are heavy compared to the electroweak scale ($M \gg m_W$), and
that are charged under electroweak SU(2) gauge interactions display universal
properties such as a characteristic fine structure in the mass spectrum induced
by electroweak symmetry breaking, and an approximately universal cross section
for scattering on nuclear targets. The heavy particle effective theory
framework is developed to compute these properties. As illustration, the spin
independent cross section for low-velocity scattering on a nucleon is evaluated
in the limit $M \gg m_W$, including complete leading-order matching onto quark
and gluon operators, renormalization analysis, and systematic treatment of
perturbative and hadronic-input uncertainties.
