  By using the Dyson-Schwinger/Bethe-Salpeter formalism in Euclidean spacetime,
we calculate the ground state spectrum of $J\leq 1$ hadrons in an SU(2) gauge
theory with 2 fundamental fermions. We show that the rainbow-ladder truncation,
commonly employed in QCD studies, is unsuitable for a description of an SU(2)
theory. This we remedy by truncating at the level of the quark-gluon vertex
Dyson-Schwinger equation in a diagrammatic expansion. Results obtained within
this novel approach show good agreement with lattice studies. These findings
emphasize the need to use techniques more sophisticated than rainbow-ladder
when investigating generic strongly interacting gauge theories.
