  We demonstrate that all tree-level string theory amplitudes can be computed
using the BCFW recursion relations. Our proof utilizes the pomeron vertex
operator introduced by Brower, Polchinski, Strassler, and Tan. Surprisingly, we
find that in a particular large complex momentum limit, the asymptotic
expansion of massless string amplitudes is identical in form to that of the
corresponding field theory amplitudes. This observation makes manifest the fact
that field-theoretic Yang-Mills and graviton amplitudes obey KLT-like
relations. Moreover, we conjecture that in this large momentum limit certain
string theory and field theory amplitudes are identical, and provide evidence
for this conjecture. Additionally, we find a new recursion relation which
relates tachyon amplitudes to lower-point tachyon amplitudes.
