  We explore the idea that the chiral phase transition in QCD can be described
as a transition from a disordered instanton liquid to a strongly correlated
phase of polarized instanton anti-instanton molecules. We find a number of non
perturbative effects caused by the presence of instantons above T_c, among them
the fact that instantons contribute to the euquation of state. We also study
how instantons affect the propagation of light quarks at high temperature and
determine the spacelike screening masses for mesons and baryons. We derive the
corresponding effective interaction and find that the interaction in the
scalar-pseudoscalar channel is attractive and four times stronger than the one
in the vector-axial-vector channel, in agreement with recent lattice QCD
simulations.
