leon simon showed that if an area minimizing hypersurface admits a cylindrical tangent cone of the form c x r, then this tangent cone is unique for a large class of minimal cones c. one of the hypotheses in this result is that c x r is integrable and this excludes the case when c is the simons cone over $s^3 x s^3$. the main result in this talk is that the uniqueness of the tangent cone holds in this case too. the new difficulty in this non-integrable situation is to develop a version of the lojasiewicz-simon inequality that can be used in the setting of tangent cones with non-isolated singularities.