  We describe a universal behavior of linear molecules excited by a periodic
train of short laser pulses under quantum resonance conditions. In a rigid
rotor the resonance causes an unlimited ballistic growth of the angular
momentum. We show that the centrifugal distortion of rotating molecules
eventually halts the growth, by causing Anderson localization beyond a critical
value of the angular momentum -- the Anderson wall. Its position solely depends
on the molecular rotational constants and lies in the range of a few tens of
hbar. Below the wall, rotational excitation oscillates with the number of
pulses due to a mechanism similar to Bloch oscillations in crystalline solids.
We suggest optical experiments capable of observing the rotational Anderson
wall and Bloch oscillations at near-ambient conditions with the help of
existing laser technology.
