  We study the physics of the Seiberg-Witten and
Argyres-Faraggi-Klemm-Lerche-Theisen-Yankielowicz solutions of $D=4$,
$\mathcal{N}=2$ and $\mathcal{N}=1$ $SU(N)$ supersymmetric gauge theory. The
$\mathcal{N}=1$ theory is confining and its effective Lagrangian is a
spontaneously broken $U(1)^{N-1}$ abelian gauge theory. We identify some
features of its physics which see this internal structure, including a spectrum
of different string tensions. We discuss the limit $N\rightarrow\infty$,
identify a scaling regime in which instanton and monopole effects survive, and
give exact results for the crossover from weak to strong coupling along a
scaling trajectory. We find a large hierarchy of mass scales in the scaling
regime, including very light $W$ bosons, and the absence of weak coupling. The
light $W$'s leave a novel imprint on the effective dual magnetic theory. The
effective Lagrangian appears to be inadequate to understand the conventional
large $N$ limit of the confining $\mathcal{N}=1$ theory.
