  It is conjectured that M-theory in asymptotically flat spacetime must be
supersymmetric, and that the observed SUSY breaking in the low energy world
must be attributed to the existence of a nonzero cosmological constant. This
would be consistent with experiment, if the {\it critical exponent} $\alpha$ in
the relation $M_{SUSY} \sim M_P (\Lambda /M_P^4)^{\alpha}$ took on the value
1/8, rather than its classical value 1/4. We attribute this large
renormalization to the effect of large virtual black holes via the UV/IR
correspondence.
