  The origin of the dichotomy of radio loudness among quasars can be explained
using recent findings that the mass of the central supermassive black hole
(SMBH) in extended radio-loud quasars is systematically a few times that of
their counterparts in radio-quiet quasars. This sensitive dependence of radio
jet ejection upon SMBH mass probably arises from the blockage of jets by the
presence of substantial quantities of gas tidally stripped from stars by the
central BH. This disruptive gas, however, will only be available around BHs
with masses less than $M_c ~\gtrsim ~10^8\Msun$, for which the tidal disruption
radius lies outside the SMBH's event horizon. Consequently, we find that AGN
with $M_{BH} > M_c$ can successfully launch jets with a wide range of powers,
thus producing radio-loud quasars. The great majority of jets launched by less
massive BHs, however, will be truncated in the vicinity of the SMBH due to mass
loading from this stellar debris. This scenario also can naturally explain the
remarkable dearth of extended radio structures in quasars showing broad
absorption line spectra.
