  The recently introduced Lipschitz-Killing curvature measures on
pseudo-Riemannian manifolds satisfy a Weyl principle, i.e. are invariant under
isometric embeddings. We show that they are uniquely characterized by this
property. We apply this characterization to prove a K\"unneth-type formula for
Lipschitz-Killing curvature measures, and to classify the invariant generalized
valuations and curvature measures on all isotropic pseudo-Riemannian space
forms.
