  The rainbow truncation of the quark Dyson-Schwinger equation is combined with
the ladder Bethe-Salpeter equation for the dressed quark-photon vertex to study
the low-momentum behavior of the pion electromagnetic form factor. With model
gluon parameters previously fixed by the pion mass and decay constant, the pion
charge radius $r_\pi$ is found to be in excellent agreement with the data. When
the often-used Ball-Chiu Ansatz is used to construct the quark-photon vertex
directly from the quark propagator, less than half of $r_\pi^2$ is generated.
The remainder of $r^2_\pi$ is seen to be attributable to the presence of the
$\rho$-pole in the solution of the ladder Bethe-Salpeter equation.
