  The distribution of isoscalar monopole strength in the neutron-even
112-124Sn-isotopes has been computed using a relativistic
random-phase-approximation approach. The accurately-calibrated model used here
(``FSUGold'') has been successful in reproducing both ground-state observables
as well as collective excitations - including the giant monopole resonance
(GMR) in 90Zr, 144Sm, and 208Pb. Yet this same model significantly
overestimates the GMR energies in the Sn isotopes. It is argued that the
question of ``Why is Tin so soft?'' becomes an important challenge to the field
and one that should be answered without sacrificing the success already
achieved by several theoretical models.
