  We reveal a deep connection between alignment of dust grains by RAdiative
torques (RATs) and MEchanical Torques (METs) and rotational disruption of
grains introduced by Hoang et al. (2019). The disruption of grains happens if
they have attractor points corresponding to high angular momentum (high-J). We
introduce {\it fast disruption} for grains that are directly driven to the
high-J attractor on a timescale of spin-up, and {\it slow disruption} for
grains that are first moved to the low-J attractor and gradually transported to
the high-J attractor by gas collisions. The enhancement of grain magnetic
susceptibility via iron inclusions expands the parameter space for high-J
attractors and increases percentage of grains experiencing the disruption. The
increase in the magnitude of RATs or METs can increase the efficiency of fast
disruption, but counter-intuitively, decreases the effect of slow disruption by
forcing grains towards low-J attractors, whereas the increase in gas density
accelerates disruption by faster transporting grains to the high-J attractor.
We also show that disruption induced by RATs and METs depends on the angle
between the magnetic field and the anisotropic flow. We find that pinwheel
torques can increase the efficiency of {\it fast disruption} but may decrease
the efficiency of {\it slow disruption} by delaying the transport of grains
from the low-J to high-J attractors via gas collisions. The selective nature of
the rotational disruption opens a possibility of observational testing of grain
composition as well as physical processes of grain alignment.
