  We prove a Morse Lemma for coarsely regular quasigeodesics in nonpositively
curved symmetric spaces and euclidean buildings X. The main application is a
simpler coarse geometric characterization of Morse subgroups of the isometry
groups Isom(X) as undistorted subgroups which are coarsely uniformly regular.
We show furthermore that they must be word hyperbolic. We introduced this class
of discrete subgroups in our earlier paper, in the context of symmetric spaces,
where various equivalent geometric and dynamical characterizations of word
hyperbolic Morse subgroups were established, including the Anosov subgroup
property.
