  It is shown that, if generators of supersymmetry transformations
(supercharges) can be defined in a spatially homogeneous physical state, then
this state describes the vacuum. Thus, supersymmetry is broken in any thermal
state and it is impossible to proceed from it by ``symmetrization'' to states
on which an action of supercharges can be defined. So, unlike the familiar
spontaneous breakdown of bosonic symmetries, there is a complete collapse of
supersymmetry in thermal states. It is also shown that spatially homogeneous
superthermal ensembles are never supersymmetric.
