  This paper explains the relation between the fusion product of symmetric
power sl(n) evaluation modules, as defined by Feigin and Loktev, and the graded
coordinate ring R(mu), which describes the cohomology ring of the flag variety
Fl(mu) of GL(N). The graded multiplicity spaces appearing in the decomposition
of the fusion product into irreducible sl(n)-modules are identified with the
multiplicity spaces of the Specht modules in R(mu). This proves that the Kostka
polynomial gives the character of the fusion product in this case. In the case
of the product of fundamental evaluation modules, we give the precise
correspondence with the reduced wedge product, and thus the usual wedge space
construction of irreducible level-1 ^sl(n)-modules in the limit N->infty. The
multiplicity spaces are W(sl(n))-algebra modules in this limit.
