  We compare the kinetic energy and momentum injection rates from intense star
formation, bolometric AGN radiation, and radio jets with the kinetic energy and
momentum observed in the warm ionized gas in 24 powerful radio galaxies at z~2.
These galaxies are amongst our best candidates for being massive galaxies near
the end of their active formation period, when intense star formation, quasar
activity, and powerful radio jets all co-exist. All galaxies have VLT/SINFONI
imaging spectroscopy of the rest-frame optical line emission, showing
emission-line regions with large velocity offsets (up to 1500 km/s) and line
widths (typically 800-1000 km/s) consistent with very turbulent, often
outflowing gas. As part of the HeRGE sample, they also have FIR estimates of
the star formation and quasar activity obtained with Herschel/PACS and SPIRE,
which enables us to measure the relative energy and momentum release from each
of the three main sources of feedback in massive, star-forming AGN host
galaxies during their most rapid formation phase. We find that star formation
falls short by factors 10-1000 of providing the energy and momentum necessary
to power the observed gas kinematics. The obscured quasars in the nuclei of
these galaxies provide enough energy and momentum in about half of the sample,
however, only if these are transfered to the gas relatively efficiently. We
compare with theoretical and observational constraints on the efficiency of the
energy and momentum transfer from jet and AGN radiation, which advocates that
the radio jet is the main driver of the gas kinematics.
