  We explore the possibility that the initial transverse momentum distribution
of unpolarized and polarized partons within unpolarized nucleons, both with and
without the anisotropy of unpolarized hadrons produced in the fragmentation of
outgoing partons, could lead to the observed azimuthal anisotropy of high
transverse momentum (high-$p_T$) hadrons produced in high energy proton-proton
($p$-$p$) or proton-ion ($p$-$A$) collisions. Including simple Gaussian forms
for transverse momentum dependent parton distribution functions (PDF) and
fragmentation functions, and assuming an $A^{1/3}$ enhancement of a PDF in
$p$-$Pb$ collisions, we show that the observed anisotropy, with \emph{no
modification} to the angle integrated spectra ($R_{pA}=1$) for 5~GeV~$\lesssim
p_T\lesssim 50$~GeV, can be straightforwardly understood as arising from a few
processes dominated by gluon-gluon to gluon-gluon scattering.
