  In an earlier paper, it is proposed that, due to resonance tunneling effect,
tunneling from a large cosmological constant $\Lambda$ site in the stringy
comic landscape can be fast, while tunneling from a small $\Lambda$ site may
take exponentially long time. Borrowing the renormalization group analysis of
the conductance in the Anderson localization transition, we treat the landscape
as a multi-dimensional random potential and find that the vastness of the
landscape leads to a sharp transition at a small critical value $\Lambda_{c}$
from fast tunneling for $\Lambda > \Lambda_{c} $ to suppressed tunneling for
$\Lambda_{c} > \Lambda >0$. Mobility in the landscape makes eternal inflation
highly unlikely. As an illustration, we find that $\Lambda_{c}$ can easily be
exponentially small compared to the string/Planck scale. These properties may
help us in finding a qualitative understanding why today's dark energy is so
small.
