  We extend our analysis in [arXiv:0801.4782] and show that the chiral algebras
of (0,2) sigma models are totally trivialized by worldsheet instantons for all
complete flag manifolds of compact semisimple Lie groups. Consequently,
supersymmetry is spontaneously broken. Our results verify Stolz's idea that
there are no harmonic spinors on the loop spaces of these flag manifolds.
Moreover, they also imply that the kernels of certain twisted Dirac operators
on these spaces will be empty under a "quantum" deformation of their
geometries.
