  The confirmation of the cluster soft excess (CSE) by XMM-Newton has rekindled
interest as to its origin. The recent detections of CSE emission at large
cluster radii together with reports of OVII line emission associated with the
CSE has led many authors to conjecture that the CSE is, in fact, a signature of
the warm-hot intergalactic medium (WHIM). In this paper we test the scenario by
comparing the observed properties of the CSE with predictions based on models
of the WHIM. We find that emission from the WHIM in current models is 3 to 4
orders of magnitude too faint to explain the CSE. We discuss different
possibilities for this discrepancy including issues of simulation resolution
and scale, and the role of small density enhancements or galaxy groups. Our
final conclusion is that the WHIM alone is unlikely to be able to accout for
the observed flux of the CSE.
